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I tested three SVBONY 2x Barlow lenses in 2021: the basic model with the camera thread, the SV137 and the SV118. I kept the SV137, and it is the one I still recommend. This update keeps my original notes, drops what Amazon no longer sells and adds the Barlows that replaced the old models. The SVBONY SV137 2x is in stock on Amazon US as of November 2026, sold by SVBONY Direct and shipped by Amazon.
Verdict
4 out of 5 as a budget Barlow
The SV137 2x doubles the power of every 1.25″ eyepiece you own. It has a metal body, a brass ring that protects eyepiece barrels and a grip ring for cold fingers. The optics are two elements with multi-coated lenses, a clear step up from the basic SVBONY Barlow. Its limits are the usual ones for a budget 2x: it will not fix a weak eyepiece, and the edge of the field softens in fast telescopes.
Still sold: yes. The SV137 2x is in stock on Amazon US (checked November 2026). The basic M42 model I tested was relisted under a new page, and the SV118 is gone.
Specs at a glance
| Model | SVBONY SV137 2x Barlow |
|---|---|
| Magnification | 2x (doubles the power of any eyepiece) |
| Barrel and eyepiece size | 1.25″ in, 1.25″ out |
| Optics | Fully multi-coated lenses, two-element design |
| Body | Black anodized aluminum, brass ring in the eyepiece end, non-slip grip ring |
| Camera thread | Male M42 T-thread on the back (a T-ring for your camera brand is sold separately) |
| Sold by | SVBONY Direct, shipped by Amazon |
| Status in 2026 | In stock on Amazon US |
The three SVBONY 2x Barlows I tested
SVBONY sells telescopes, binoculars and accessories aimed at beginners. In 2021 its Barlow line had three 2x models at different build levels. Here is where each one stands now.
| Model | Status in 2026 | Build | My verdict | Link |
|---|---|---|---|---|
| SVBONY 2x with M42 thread (basic) | Old page discontinued, current page in stock | Aluminum, thumbscrew, M42 thread | Only on a tight budget | Check on Amazon |
| SVBONY SV137 2x | In stock | Brass ring, grip ring, two elements | The best of the three | Check on Amazon |
| SVBONY SV118 2x | No longer sold | Metal case | No gain over the SV137 | Not available |
What a Barlow does
A Barlow lens sits between the telescope and the eyepiece and doubles the focal length of the telescope. A 2x Barlow turns a 20mm eyepiece into the equivalent of a 10mm one, and you keep the long eye relief of the 20mm. With three eyepieces and a Barlow you have six powers. The same field of view shows half as much sky, so a Barlow is for the Moon and planets more than for wide star fields. The full explanation is in my Barlow lens guide, and Barlow lens vs eyepiece covers when to buy one instead of another eyepiece.
Every extra piece of glass can cost a little light and add false color or reflections. The test for a Barlow is that after it goes in, the image looks like a bigger version of the same image.
SVBONY SV137 2x: build and fit
The SV137 is a black aluminum tube with a knurled band in the middle. The grip ring is plastic, not rubber like the ones on Celestron’s pricier Barlows, but it keeps the lens from slipping in a cold hand. Inside the eyepiece end is a brass ring. It sits between the thumbscrew and the eyepiece, so the screw does not bite into the barrel of your eyepiece. That is the biggest build difference from the basic model, where the screw presses on bare metal.
The Barlow slides into the 1.25″ holder of a star diagonal or focuser and takes the eyepiece in its top end. Refocus after you insert it, because the focus point moves each time. The back of the SV137 carries an M42 T-thread, so with the right T-ring and adapter it connects a camera body. I did not use it that way. If cameras are your goal, look at the SV216 below.
Image quality
I took the SV137 apart to look at the lenses. It has two elements, and the basic model I tested had one. The glass looks better finished, and that shows at the eyepiece. Against the basic model the SV137 gave a cleaner image on the Moon and on Jupiter, with less haze around bright objects.
Color is neutral. On the Moon the limb stays sharp, and Jupiter’s belts show without color fringes at moderate power. I used it in a 70mm refractor and a 130mm reflector. In both, the useful range was a 15mm or longer eyepiece behind the Barlow. The edge of the field goes soft in a fast telescope, as it does with every 2x Barlow at this level, and stars in the center focus to points, which is what matters for planets.
To work out your own powers, divide the telescope focal length by the eyepiece focal length and multiply by two. A 650mm telescope with a 15mm eyepiece gives 43x, and 87x with the Barlow. My magnification chart and magnification calculator do the sums for you, and the Omni review has a table of Barlow powers for four common telescopes.
The basic SVBONY 2x with the camera thread
This was the cheapest of the three and the one I rated lowest. The multi-coating is weaker than on pricier Barlows, though having any multi-coating at this level is a plus. The listing promised blackened edges, but on my sample they were not dark enough to notice, and that cost it points. Colors and brightness were fine for a beginner who is not yet picking out small detail.
The camera thread is the feature SVBONY promotes, but I would not pair this unit with an expensive DSLR. The optics hold back the images, and the SV137 has the same thread. The listing I bought is discontinued. The current page for the basic model is B00WW0TC32, which Amazon lists as an aluminum 2x with the same M42 thread. I have not handled that exact unit. Buy it only if you want the lowest-cost 2x or a body to modify for a DIY project.
The SV118
The SV118 was SVBONY’s metal-cased 2x in the same family. It looked like an SV137 in a nicer case, and I saw no gain in the optics. It is no longer sold, and the SV137 is the better value of the two.
What I did not like
- A plastic grip ring. It helps, but rubber on a Celestron X-Cel LX holds better in damp weather.
- Soft edges in fast telescopes. In an f/5 reflector the outer part of the field is blurry. This is common to 2x Barlows at this level.
- No filter thread that I could confirm. The listing does not say the barrel takes filters, so put filters on the eyepiece.
- Not a fix for a weak eyepiece. A Barlow multiplies what the eyepiece gives it, flaws included.
Pros and cons
Pros
- Two-element, multi-coated optics, better than the basic SVBONY
- Brass ring protects eyepiece barrels
- Metal body with a non-slip ring
- M42 T-thread for camera adapters
- Fits every 1.25″ focuser, diagonal and eyepiece
- Brass ring on a budget Barlow
Cons
- Plastic grip ring, not rubber
- Soft field edge in fast telescopes
- Only 2x, so no extra reach for short telescopes
- Camera use needs a separate T-ring
- No confirmed filter thread in the barrel
What to buy instead
The SV137 2x suits most people with a 70mm to 150mm telescope. Four situations call for something else: a 3x for a short telescope, a four-element SVBONY for cameras, the Celestron Omni if you want a longer warranty, or a premium telecentric 2x. All four picks below are in stock on Amazon US as of November 2026. My ranked list of every option is in the best Barlow lenses guide.
| Barlow | Multiplier | Design | Link |
|---|---|---|---|
| SVBONY SV137 2x (reviewed) | 2x | Two elements, brass ring | Check on Amazon |
| SVBONY SV137 3x | 3x | Brass ring, rubber grip | Check on Amazon |
| SVBONY SV216 2x | 2x | Four-element telecentric | Check on Amazon |
| Celestron Omni 2x | 2x | Metal body, 2-year warranty | Check on Amazon |
| Explore Scientific 2x | 2x | Telecentric focal extender | Check on Amazon |
For short telescopes
SVBONY SV137 3x Barlow
The 3x version of the SV137 has the same brass compression ring and a rubber grip ring in place of the plastic one. The lens edges are blackened and the lenses are fully multi-coated. A 3x gives more power from each eyepiece, which helps a short telescope such as a small refractor with a 400mm focal length. Past that it runs out of room fast: a 15mm eyepiece in a 700mm telescope gives 140x. For a long 70mm refractor, stay with the 2x. I have not used this one.
- Multiplier: 3x, 1.25″ eyepieces
- Choose it if: your telescope has a short focal length or a large aperture and you want planetary power
Best SVBONY for cameras
SVBONY SV216 2x Barlow
The SV216 is now the top of the SVBONY 2x line. It has four elements in a telecentric design, so the magnification stays at 2x wherever it sits in the light path. The listing describes fully multi-coated lenses with blackened edges and a three-screw lock. That is the Barlow in the SVBONY line to pair with a camera. I have not used it. It only pays off in a larger telescope or with imaging.
- Multiplier: 2x, 1.25″ eyepieces, four elements
- Choose it if: you image the Moon and planets, or you own a telescope with 150mm of aperture or more
Longer warranty
Celestron Omni 2x Barlow
The Omni is the Barlow I reach for first, and I wrote it up in its own Celestron Omni 2x Barlow review. It is a plain metal 2x with blackened lens edges, and Celestron backs it with a 2-year US warranty. Against the SV137 it has no brass ring and no camera thread. The optics are close, so the choice comes down to the warranty and the camera thread.
- Multiplier: 2x, 1.25″ eyepieces, threaded barrel
- Choose it if: you want a US warranty and have no plan to use a camera
Premium pick
Explore Scientific 2x Focal Extender
This is a telecentric 2x with several lens elements. Amazon lists it at 96mm long and 260 grams, which is heavy for a Barlow. It is the most expensive pick here. The telecentric design keeps the magnification constant and helps eye relief and field flatness, and it is made for people with larger telescopes who want the sharpest field. I have not used it. On a small refractor the weight can upset the balance.
- Multiplier: 2x, 1.25″ eyepieces, telecentric
- Choose it if: you own a 200mm or larger telescope and want the best field you can buy in a 2x
I dropped the Orion Shorty 2x that my 2021 review suggested. Amazon shows it as discontinued.
Add-ons worth getting
These two work with any 2x Barlow and fit 1.25″ focusers.
Best eyepiece to pair
SVBONY SV135 7mm to 21mm Zoom Eyepiece
A zoom eyepiece behind a 2x Barlow doubles the power across its whole range. Keep the zoom toward its long end, so that the combined power stays within what your telescope can handle. My zoom eyepiece guide compares the options, and zoom vs fixed eyepieces explains the trade-offs.
For the Moon
SVBONY SV139 ND8 Moon Filter
The Moon at 100x or 150x is bright enough to hurt. This neutral density filter passes 12.5% of the light and threads into the bottom of a 1.25″ eyepiece, where it cuts glare without changing color. Read do you need a Moon filter before buying one.
Final word
Of the three SVBONY Barlows I tested in 2021, the SV137 2x is the one worth buying. It costs little more than the basic model and gives a better image, a protected eyepiece barrel and a body that lasts. Pick the SV137 3x for a short telescope and the SV216 if you want to take pictures. Pick the Omni if a 2-year warranty matters more to you than a camera thread.
More from Little Astronomy
- Barlow lens: everything you need to know
- Best Barlow lenses
- Celestron Omni 2x Barlow review
- Best budget telescope eyepieces
- Best eyepieces for planets
FAQ
Is the SVBONY SV137 2x Barlow still available?
Yes. As of November 2026 it is in stock on Amazon US, sold by SVBONY Direct and shipped by Amazon. The basic SVBONY 2x with the camera thread has a new page, and the SV118 is no longer sold.
Is the SVBONY Barlow lens good?
The SV137 2x is good for a budget Barlow. It doubles the power of any 1.25″ eyepiece with neutral color on the Moon and Jupiter, and its brass ring protects your eyepieces. The basic model is weaker, with thinner coatings and edges that were not visibly blackened on my sample.
Which SVBONY Barlow should I buy?
The SV137 2x for most telescopes from 70mm to 150mm. Choose the SV137 3x for a short telescope and the SV216 2x if you take photos through the telescope.
What happened to the SVBONY SV118 Barlow?
It is no longer sold on Amazon US. The SV216 now fills the top of the SVBONY 2x line. In my tests the SV118 looked like an SV137 in a better case with no gain in optics.
SVBONY SV137 2x or 3x?
Take the 2x unless your telescope is short or large. A 3x pushes each eyepiece to high power quickly, and a small lens runs out of light and sharpness. In a short telescope or a 130mm and larger telescope, the 3x is useful with a 15mm or longer eyepiece.
Can I use an SVBONY Barlow for photography?
The SV137 2x lists a male M42 T-thread on the back. With a T-ring for your camera brand and a T-adapter it connects a DSLR or mirrorless body. Phone photos through the eyepiece also work. For serious imaging, the four-element SV216 is the better SVBONY choice.
SVBONY or Celestron Omni?
The SV137 2x adds a brass ring and a camera thread. The Omni adds a 2-year US warranty and Celestron support. The image is close, so pick on those two features. My Omni review has the details.
What eyepieces work best with a Barlow?
Eyepieces of 15mm and longer. They land at 7.5mm to 16mm equivalent, a range that gives good power on the Moon and planets. A 4mm or 6mm eyepiece behind a Barlow usually gives more power than the telescope can use.
Does a Barlow lens reduce image quality?
A good one does not reduce it in any way you can see at the eyepiece. A poor one adds color fringes, reflections and dimming. Multi-coated lenses and blackened edges keep those problems low.
