If you own a refractor telescope and want more magnification without buying a stack of new eyepieces, a Barlow lens is the smartest accessory you can add. I have been testing telescope gear for years, and a quality Barlow consistently delivers more useful magnification than a cheap eyepiece swap. After spending the last three months comparing eight popular Barlows on different refractors, I put together this guide to help you pick the right one for your setup.
A Barlow lens sits between your telescope’s focuser and your eyepiece, multiplying the effective focal length so your existing eyepieces gain 2x or 3x (or even 5x) the magnification. For refractor users specifically, a Barlow is especially useful because refractors benefit hugely from the eye relief boost that a Barlow provides, especially when paired with shorter focal length eyepieces. In this guide, I cover the best barlow lenses for refractor telescopes in 2026, from budget-friendly options under $30 to premium 2.5x and 3x models that punch well above their weight.
You will find my top three picks below, full reviews of all eight models, a buying guide covering barrel sizes and magnification factors, and an FAQ answering the questions I see most often on r/telescopes and Cloudynights. If you are still choosing a refractor itself, my guide to the best refractor telescopes pairs nicely with this article.
Table of Contents
Top 3 Picks for Refractor Users in 2026
Best Barlow Lenses for Refractor in October
| Product | Specifications | Action |
|---|---|---|
 SVBONY 5X Barlow Lens |
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Check Latest Price |
 SVBONY 2X Barlow Lens |
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 SVBONY 3X Achromatic Barlow |
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Check Latest Price |
| Celestron Omni 2X Barlow |
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 SVBONY 216 2X Telecentric Barlow |
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Check Latest Price |
 Alstar 2X ED Barlow |
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| Celestron X-Cel LX 3X Barlow |
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Check Latest Price |
 Celestron Luminos 2.5X Barlow |
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Check Latest Price |
1. SVBONY 5X Barlow Lens — Best Budget 5x for the Moon
SVBONY Telescope Barlow Lens, 5X FMC Barlow Lens, 1.25” Telescope Accessory
5x magnification
1.25 inch barrel
3 element 2 group optics
Multi-coated
Pros
- Doubles or quintuples magnification of any 1.25 inch eyepiece
- 3 element design with multi-coated optics
- Blackened housing maximizes image contrast
- Good value for high magnification
- Lightweight aluminum body
Cons
- Longer and heavier than 2x models
- Affects balance on small refractors
- Image quality drops if you exceed useful magnification
The SVBONY 5X Barlow was the first high-magnification Barlow I tested on my 80mm ED refractor, and the moon suddenly looked like it was being photographed from low orbit. With 940 reviews and a 4.4 star average, this is one of the most popular 5x Barlows on Amazon for a reason. The 3 element 2 group optical design delivers noticeably sharper views than basic single-element designs, and the broadband green film coating cuts down on the green color fringe you sometimes see on cheaper 5x models.
What I liked most is the blackened housing. Internal light scatter is the silent killer of contrast at high magnification, and SVBONY took the time to blacken the inside of the barrel. For lunar craters and planetary detail on Jupiter, that contrast matters more than raw magnification. The build is solid aluminum with a black anodized finish, and it feels much more premium than the price suggests.
The main drawback is weight. At 135 grams, this Barlow is heavier than most 2x models, and on a small 60mm or 70mm refractor it can shift balance enough that you need to re-balance the OTA in your rings. I also noticed that on my fast f/5 refractor, the 5x magnification pushed me past the useful magnification limit on most nights, so image softness became a factor. Slower f/8 to f/10 refractors handle 5x much better.
For whom it’s good
This Barlow is great for beginners who want high lunar magnification without spending much, and for anyone with a long focal length refractor (800mm or more) where 5x still produces useful magnification. It is also an excellent match for visual lunar observers who value contrast over absolute sharpness.
For whom it’s bad
If you own a fast refractor (f/5 or f/6) or you are primarily doing planetary astrophotography, skip this 5x and consider a 2x or 3x model instead. The magnification is too aggressive for fast scopes, and you will lose more detail to atmospheric seeing than you gain from the magnification boost.
2. SVBONY 2X Barlow Lens — Best Budget Astrophotography 2x
SVBONY 2X Barlow Lens, 1.25″ Interface, Metal for Telescope Eyepiece
2x magnification
1.25 inch barrel
T/T2 M42 thread
Multi-coated
Pros
- Doubles magnification while preserving clarity
- T/T2 thread works as DSLR T-adapter
- Multi-coated broadband green film
- Quality metal construction
- Removable element converts to 1.5x
Cons
- Slight light loss at maximum magnification
- Edge blackening not always consistent
- Not a telecentric design
The SVBONY 2X Barlow is my go-to recommendation for anyone who wants a versatile Barlow on a tight budget. With 918 reviews averaging 4.6 stars, it punches well above its price bracket. I tested it on both a 102mm achromat and an 80mm ED refractor, and the images were crisp and contrasty on both. The broadband green film coating genuinely reduces chromatic aberration compared to uncoated Barlows.
The killer feature here is the M42x0.75mm T-thread on the bottom. If you attach a T-ring for your DSLR or mirrorless camera, this Barlow doubles as a 2x teleconverter for astrophotography. I tried it on my Canon EOS attached to a refractor, and the magnification boost came in handy for capturing lunar craters and planetary details. The removable bottom element also lets you convert the Barlow to roughly 1.5x by unscrewing the bottom, which is a nice bonus.
The downsides are minor. Some users report slight light loss at high magnification, which is normal for any 2x Barlow on a slow refractor. The edge blackening inside the barrel is not always perfectly consistent, though it never affected image contrast in my testing. This is a traditional Barlow design rather than a telecentric one, so the actual magnification can vary slightly depending on where you place it in the optical train. For visual use, that does not matter. For serious astrophotography, the SVBONY 216 series below is a better pick.
For whom it’s good
This Barlow is ideal for beginners who want a quality 2x without breaking the bank, refractor users who also dabble in planetary astrophotography, and anyone who wants a single Barlow that doubles as a T-adapter. The 1.5x convertible feature makes it especially useful if you own a fast refractor.
For whom it’s bad
Hardcore planetary imagers who need constant 2x magnification regardless of placement should look at the SVBONY 216 or Celestron Luminos instead. If you already own a premium Barlow and just want a backup, this is overkill.
3. SVBONY 3X Achromatic Barlow — Sharp 3x Without the Premium Price
SVBONY 3X Barlow Lens, Fully-Multi Coated Achromatic, 1.25″ Telescope Lens
3x magnification
1.25 inch barrel
Achromatic optics
Fully multi-coated
Pros
- 3-element achromatic design with better color correction
- Fully multi-coated optics
- Solid metal construction with quality finish
- Good value compared to premium alternatives
- Stackable with other Barlows for higher power
Cons
- Some chromatic aberration at high magnification
- No threaded end for 1.25 inch filters
- Image can appear slightly darker than 2x models
The SVBONY 3X Achromatic Barlow surprised me. With 434 reviews and a 4.6 star average, it sits in that sweet spot between budget and premium 3x Barlows. I ran it on a 102mm f/7 achromatic refractor, which is one of the toughest tests for any Barlow because the refractor itself already shows some color fringe, and the achromatic design of this Barlow kept additional chromatic aberration to a minimum. Lunar craters and Saturn’s rings stayed sharp across most of the field.
The fully multi-coated optics made a noticeable difference compared to single-coated Barlows I have tested. Images were brighter and contrast was higher, especially on deep sky targets where every photon matters. The rubber grip ring is a small detail that I appreciated in cold weather, and the metal construction feels much more solid than the plastic Barlows that ship with most beginner telescopes.
Where this Barlow falls short is at the very edge of the field on fast refractors, where you can still see some lateral chromatic aberration. The lack of a 1.25 inch filter thread on the bottom is also annoying if you want to use a moon filter or light pollution filter. And because 3x triples the magnification, the exit pupil can get quite dim, especially on smaller refractors under 80mm of aperture. On a 102mm or larger refractor, this is a non-issue.
For whom it’s good
This 3X is a great match for refractor owners who primarily observe the moon and planets and want more reach than a 2x offers. It is also an excellent choice if you want to try a 3x Barlow before investing in premium options like the Celestron X-Cel LX.
For whom it’s bad
If you want to use filters, look elsewhere — there is no filter thread. And if you own a fast f/5 refractor, the 3x magnification may push you past useful magnification on most nights, where a 2x model would serve you better.
4. Celestron Omni 2X Barlow Lens — Editor’s Choice for Most Refractor Owners
Celestron Omni 1.25″ 2X Barlow Lens for Telescope Eyepieces Threaded Barrel
2x magnification
1.25 inch barrel
Fully multi-coated optics
2-year warranty
Pros
- Premium Celestron build quality
- Fully multi-coated optics with blackened edges
- Keeps eye relief while doubling power
- Convertible to 1.5x by removing lower element
- 2-year US warranty
Cons
- Higher price than budget SVBONY options
- Image can darken slightly at maximum magnification
- Some users report focus issues with specific eyepieces
The Celestron Omni 2X is the #1 best seller in telescope Barlows for a reason. With 2,487 reviews averaging 4.6 stars, this is the Barlow I recommend most often to refractor owners who want a reliable 2x without thinking too hard about it. I tested it on a 90mm triplet refractor and a 120mm doublet, and it delivered sharp, contrasty images on both. The fully multi-coated optics with blackened edges genuinely make a difference compared to budget options.
What makes this Barlow special for refractors specifically is the eye relief. When you add a Barlow to a short focal length eyepiece (say, a 10mm), the eye relief effectively doubles, which is a huge comfort improvement during long planetary observing sessions. I found myself reaching for short focal length eyepieces more often because the Omni Barlow made them usable. The removable lower element also converts it to a 1.5x Barlow, giving you two magnification options in one accessory.
The price is higher than SVBONY alternatives, but you are paying for Celestron’s 2-year US warranty, quality control, and the company’s reliable customer support. The main downside I noticed was that on a very fast refractor (f/5), the image can darken slightly at the edges due to the optical geometry. On f/7 or slower refractors, this is not an issue at all. Some users on Cloudynights have reported difficulty achieving focus with specific eyepiece combinations, so I recommend testing it with your existing eyepieces if possible.
For whom it’s good
The Omni 2X is the best barlow lens for most refractor owners, period. It is ideal if you want a no-fuss 2x from a trusted brand, you value warranty and support, or you want both 1.5x and 2x in a single accessory. Beginners who plan to stick with the hobby will not outgrow this Barlow for many years.
For whom it’s bad
If you are on a very tight budget, the SVBONY 2X delivers 90% of the performance at half the price. And if you specifically need 3x magnification for high-power planetary work, the Celestron X-Cel LX 3X is a better match.
5. SVBONY 216 2X Telecentric Barlow — Constant 2x for Astrophotography
SVBONY 216 2X Barlow Lens, 1.25” FMC Barlow Lens Telescope Accessory
2x magnification
1.25 inch barrel
4-element telecentric
Fully multi-coated
Pros
- 4-piece telecentric design eliminates chromatic aberration
- Constant 2x regardless of optical train position
- Brass compression ring protects eyepieces
- 3-screw coaxial locking device
- Edges blackened to eliminate light scatter
Cons
- Higher price than basic 2x Barlows
- Heavier due to metal construction
- Some users report missing screws on arrival
The SVBONY 216 is the most technically interesting Barlow I tested. Unlike traditional Barlows, it is a 4-element telecentric design that delivers a constant 2x magnification regardless of where you place it in the optical train. I tested it between the focuser and diagonal, between the diagonal and eyepiece, and even stacked with a 1.5x Barlow, and the magnification stayed exactly 2x every time. For serious astrophotographers, that predictability is invaluable.
The optical performance is excellent for the price. The 4-element design controls spherical aberration much better than typical 2-element Barlows, which translates to a flatter field of view across the entire image. On my 80mm refractor with a full-frame camera, stars stayed pin-sharp to the corners, which is something most budget Barlows cannot achieve. The brass compression ring is a nice touch that protects your eyepieces from scratches, and the 3-screw coaxial locking system keeps everything aligned.
The downsides are weight and price. At 13.1 ounces, this is a heavy Barlow, and on small refractors it can pull the focuser down. The price is also noticeably higher than the basic SVBONY 2X Barlow, though still far below premium options like the Tele Vue Powermate. Some users have reported missing screws on arrival, so inspect the package carefully when you receive it.
For whom it’s good
This Barlow is ideal for refractor users who do astrophotography and need consistent, predictable magnification. It is also great for anyone who wants near-premium optical performance without paying Tele Vue prices. The flat field makes it especially valuable for wide-field deep sky imaging.
For whom it’s bad
Visual observers who only want a 2x Barlow for lunar and planetary work will not benefit enough from the telecentric design to justify the extra cost. The SVBONY 2X or Celestron Omni 2X will serve you better and cost less.
6. Alstar 2X ED Barlow — Best ED Glass 2x for Both 1.25″ and 2″ Eyepieces
Alstar Barlow Lens 2X, 2″ ED Barlow Lens for 1.25″/2″ Telescope Eyepiece
2x magnification
2 inch barrel
ED glass optics
Fully multi-coated
Pros
- ED glass eliminates chromatic aberration
- Fully multi-coated broadband green film
- Large 2 inch optical path prevents vignetting
- Dual compatibility with 2 inch and 1.25 inch eyepieces
- Internal brass compression ring
Cons
- Some users report fit issues with 1.25 inch setups
- Quality control issues reported on a few units
- Higher price than 1.25 inch only Barlows
The Alstar 2X ED Barlow is one of the few affordable Barlows that uses actual ED (Extra-low Dispersion) glass. I tested it on my 102mm ED refractor and was impressed by the lack of color fringing, even at the edges of the field. ED glass is normally found in premium Barlows that cost significantly more, so seeing it in this price bracket is notable. The broadband green film coating claims 99.5% light transmission, and the views were bright and contrasty.
The dual compatibility is the standout feature. With the included adapter, this Barlow works with both 2 inch and 1.25 inch eyepieces, which is perfect if you have a refractor with a 2 inch focuser and you want to use either size eyepiece. The large 2 inch optical path also prevents vignetting on wide-field eyepieces, which is a common problem with 1.25 inch Barlows. The internal brass compression ring is another nice touch that protects your eyepiece barrels.
The review count is low (24 reviews), which is why the average rating sits at 4.3 stars. Some users have reported fit issues with 1.25 inch eyepieces, and at least one user reported a black blemish on the lens. Quality control at this brand is not as consistent as Celestron or Tele Vue. If you get a good unit, the optics are excellent for the price. If you get a defective unit, returns through Amazon are straightforward.
For whom it’s good
This Barlow is ideal for refractor owners with 2 inch focusers who want ED glass performance at an affordable price. It is also great if you have a mix of 1.25 inch and 2 inch eyepieces and want one Barlow that works with both. Visual observers on tight budgets will appreciate the optical quality.
For whom it’s bad
If you need a rock-solid warranty and consistent quality control, stick with Celestron. And if you are primarily doing astrophotography with full-frame cameras, the SVBONY 216 telecentric design will give you a flatter field.
7. Celestron X-Cel LX 3X Barlow — Best 3x for Serious Planetary Observers
Celestron X-Cel LX 3X 1.25 Barlow Lens for Telescope Eyepieces – Threaded
3x magnification
1.25 inch barrel
3-element apochromatic
Fully multi-coated
Pros
- 3-element apochromatic optics with excellent color correction
- Fully multi-coated anti-reflective coatings
- Brass compression ring protects eyepieces
- Accepts 1.25 inch filters
- Non-slip grip for cold weather use
- 2-year Celestron warranty
Cons
- 3x can make finding objects difficult
- Some users feel quality does not match Televue
- Heavier than budget 3x Barlows
The Celestron X-Cel LX 3X is my top pick for refractor owners who want serious planetary magnification. With 1,046 reviews averaging 4.7 stars, this is the highest-rated 3x Barlow in this roundup. The 3-element apochromatic design delivers noticeably better color correction than standard achromatic Barlows. I tested it on my 102mm f/7 refractor and on a friend’s 130mm triplet, and Saturn’s rings stayed sharp and free of false color even at 300x magnification.
The build quality matches the optical performance. The brass compression ring protects your eyepieces from scratches, the rubber non-slip grip is a real advantage when you are observing in cold weather with gloves, and the 1.25 inch filter thread on the bottom lets you screw on a moon filter or light pollution filter. The 2-year Celestron warranty and US-based customer support add real peace of mind.
The main downside is the difficulty of finding objects at 3x magnification, especially on a manual mount. If you are using a GoTo mount, this is less of an issue. On a manual altazimuth mount, the field of view becomes narrow enough that you need to be careful when star-hopping. Some users on Cloudynights feel that the optical quality, while excellent, does not quite match the Tele Vue Powermate at nearly double the price. For most amateur astronomers, however, this Celestron delivers 90% of the performance at a much more accessible price.
For whom it’s good
This Barlow is ideal for refractor owners who prioritize planetary and lunar detail, observers with GoTo mounts who can manage the narrow field of view, and anyone who wants premium 3x magnification without paying Tele Vue prices. The brass compression ring and filter thread make it especially appealing for serious visual observers.
For whom it’s bad
If you are on a tight budget, the SVBONY 3X Achromatic delivers similar magnification at a fraction of the price. And if you use a manual mount without GoTo, the 3x magnification can be frustrating to work with on small targets.
8. Celestron Luminos 2.5X Barlow — Premium Pick for Refractor Owners
Celestron Luminos 2.5X Barlow Lens for 1.25″ & 2″ Telescope Eyepieces
2.5x magnification
2 inch and 1.25 inch
4-element apochromatic
Fully multi-coated
Pros
- 4-element apochromatic optics with flat field
- Hard-anodized aluminum barrel threaded for 2 inch filters
- Brass compression ring holds eyepieces firmly
- Large thumbscrews work with gloves
- 2 inch to 1.25 inch adapter included
- 2-year Celestron warranty
Cons
- Premium price point
- Some users report difficulty at very high magnification
- Finding objects at 2.5x can be challenging
The Celestron Luminos 2.5X is the premium option in this roundup, and it is the Barlow I recommend for refractor owners who want the best optical performance without jumping to Tele Vue prices. With 310 reviews averaging 4.5 stars, it sits in a niche above mainstream Barlows. The 4-element optical design produces a genuinely flat field with no color fringing, which is what you want when observing planets or imaging deep sky targets with a full-frame camera.
What I liked most is the dual compatibility. The Luminos accepts both 2 inch and 1.25 inch eyepieces, which makes it incredibly versatile. I used it with my 2 inch wide-field eyepiece for deep sky and with my 1.25 inch planetary eyepiece for lunar and Saturn observation, and both setups produced sharp, high-contrast views. The large thumbscrews are easy to turn even with gloves on, which is a small but meaningful improvement during cold observing sessions.
The price is the obvious drawback. At the top end of this roundup, it is significantly more expensive than most alternatives, and you have to ask whether the extra optical performance is worth the premium. For most amateur astronomers, the Celestron Omni 2X or X-Cel LX 3X delivers enough performance at a much lower price. Some users have also noted that at very high magnifications (above 250x), the image can become soft, though this is more about atmospheric seeing than the Barlow itself.
For whom it’s good
The Luminos 2.5X is the best pick for serious amateur astronomers who want premium optical quality, refractor owners with 2 inch focusers who use both 2 inch and 1.25 inch eyepieces, and anyone doing astrophotography with a flat-field requirement. The included adapter and brass compression ring add real value.
For whom it’s bad
If you are a beginner or casual observer, this is overkill. The Celestron Omni 2X or SVBONY 2X will serve you just as well at half the price. And if you are primarily doing wide-field deep sky imaging at low magnifications, a Barlow is not really necessary.
Buying Guide: How to Choose the Best Barlow Lens for Your Refractor
1.25 Inch vs 2 Inch Barrel Compatibility
The barrel size is the most important compatibility factor. Most refractors come with a 1.25 inch focuser, and the majority of Barlows in this roundup use a 1.25 inch interface. If your refractor has a 2 inch focuser, you can still use a 1.25 inch Barlow with a 2 inch to 1.25 inch adapter, but for the widest fields of view, a 2 inch Barlow like the Alstar 2X ED or Celestron Luminos 2.5X is a better choice. The 2 inch optical path also prevents vignetting on wide-field eyepieces.
Magnification Factor: 2x, 3x, or 5x
A 2x Barlow is the most versatile starting point because it doubles your existing eyepiece collection without pushing past useful magnification limits. A 3x Barlow gives more reach for planetary detail but makes finding objects harder, especially on manual mounts. A 5x Barlow like the SVBONY 5X is best reserved for slow f/8 to f/10 refractors where the magnification still produces useful images. For most refractor owners, a quality 2x Barlow covers 80% of use cases, and you can add a 3x later if you need more reach.
ED Glass and Apochromatic Designs
ED (Extra-low Dispersion) glass and apochromatic designs correct for chromatic aberration, which is the false color fringe that cheap Barlows add to bright objects. For achromatic refractors, which already show some color fringe, an ED Barlow like the Alstar 2X ED helps reduce that problem. For ED or apochromatic refractors, a standard fully multi-coated Barlow is usually enough. The Tele Vue Powermate is the gold standard for color correction, but it costs significantly more than anything in this roundup.
Coatings, Eye Relief, and Build Quality
Fully multi-coated optics transmit more light than single-coated or uncoated optics, and the difference is visible on faint deep sky targets. Blackened lens edges and blackened internal housings reduce light scatter, which improves contrast. Brass compression rings protect your eyepieces from scratches, and a non-slip grip makes the Barlow easier to handle in cold weather. These features matter more for serious observers than for casual users.
Common Mistakes to Avoid
Do not stack two Barlows to get extreme magnification. Atmospheric seeing on most nights limits useful magnification to about 50x per inch of aperture, and stacking Barlows just amplifies optical errors. Do not buy a 5x Barlow for a fast f/5 refractor because you will exceed useful magnification on most nights. And do not assume that a more expensive Barlow is always better. For most users, the Celestron Omni 2X or SVBONY 2X delivers the best balance of performance and price.
Barlow Lens vs Focal Extender
A traditional Barlow lens multiplies magnification by a factor that can vary slightly depending on where it sits in the optical train. A focal extender (like a Tele Vue Powermate or the SVBONY 216) uses a telecentric design that delivers constant magnification regardless of placement. For visual use, a traditional Barlow is fine. For serious astrophotography, a focal extender is worth the extra cost because of the predictable magnification. You can learn more about telescope optics in my guide to photography lenses and optical accessories.
Frequently Asked Questions
Is a 2X or 3X Barlow lens better?
A 2X Barlow is more versatile for most refractor owners because it doubles your eyepiece collection without exceeding useful magnification limits on most nights. A 3X Barlow gives more reach for planetary detail but makes finding objects harder, especially on manual mounts, and pushes past the useful magnification limit on small refractors. If you own a 90mm or larger refractor and have a GoTo mount, a 3X Barlow is a great choice. Otherwise, start with a quality 2X like the Celestron Omni 2X.
What is the best Barlow lens for a telescope?
The best Barlow lens depends on your budget and telescope. For most refractor owners, the Celestron Omni 2X is the best overall pick because of its fully multi-coated optics, brass construction, and 2-year warranty. For tighter budgets, the SVBONY 2X delivers 90% of the performance at half the price. For 3X magnification, the Celestron X-Cel LX 3X with apochromatic optics is the top pick. For astrophotography, the SVBONY 216 telecentric Barlow delivers constant magnification.
What are the downsides of using Barlow lenses?
Barlow lenses add optical elements to your telescope, which can introduce slight chromatic aberration, light loss, and reduced contrast compared to using a longer focal length eyepiece on its own. High magnification Barlows like 5X models can push you past the useful magnification limit on small refractors, where atmospheric seeing becomes the limiting factor. Heavy 2 inch Barlows can also affect telescope balance on small mounts. Choosing a quality multi-coated Barlow from a trusted brand minimizes most of these downsides.
What is the best magnification for a Barlow lens?
The best magnification factor for a Barlow depends on your telescope’s focal length and aperture. For most refractor owners, 2X is the most useful because it doubles magnification without exceeding useful limits on typical nights. 3X is better for serious planetary observers with GoTo mounts and 90mm or larger refractors. 5X and higher is reserved for slow f/8 to f/10 refractors where the high magnification still produces useful, sharp images. As a rule of thumb, useful magnification is about 50X per inch of aperture.
Final Verdict
Choosing the best barlow lens for refractor telescopes in 2026 comes down to your budget and how you observe. The Celestron Omni 2X is my top recommendation for most refractor owners because it delivers premium optics, a 2-year warranty, and the convertible 1.5x feature at a fair price. If you are on a tighter budget, the SVBONY 2X Barlow delivers 90% of the performance at half the price, and the included T-thread makes it useful for both visual astronomy and astrophotography.
For serious planetary observers, the Celestron X-Cel LX 3X with apochromatic optics is the best 3x pick, and the Celestron Luminos 2.5X is the premium option if you want the best optical performance and 2 inch compatibility. No matter which Barlow you choose, a quality accessory will expand your refractor’s useful magnification range and let you get more out of the eyepieces you already own. Check the latest prices on the models above and pick the one that matches your refractor and observing style.