It multiplies the focal length, and the eye relief survives · review
SVBONY's metal 2x Barlow: a cemented two-element, one-group design with broadband green multi-coating, a blackened housing and an M42 × 0.75 thread that takes a camera T-ring.
SVBONY publishes the optical layout: two elements in one group, which means a cemented achromatic doublet. That is the classic Barlow design, and it is enough for 2x on most telescopes used visually.
Few Barlow listings at this price give an element count at all.
The glass is described as broadband green-film multi-coated, with a blackened housing to cut stray light. The green is the color the coating reflects; it signals a multi-layer coating without saying how many layers.
The aluminum body is black anodized and carries an M42 × 0.75 mm thread. With a T-ring for your camera, the Barlow becomes a camera adapter that also adds focal length. The T-ring is sold separately.
SVBONY pitches it as doubling an existing eyepiece set at the cost of one eyepiece. With a 25 mm and a 10 mm on a 900 mm telescope, the Barlow adds 72x and 180x to the 36x and 90x already in hand.
Eye relief behavior, length and weight; Amazon’s item data gives 91 g (3.2 oz).
On November 7, 2026, Amazon.com listed it at about $18 from a third-party seller.
Figures as Keepa reported them on the day this page was last updated. Stock and pricing shift without warning.
Prices quoted in this text were read on November 7, 2026. The live price is at the top of the page.
Same aisle, closest price — what the same spend else shows.
| Amplification factor | 2x, stated |
|---|---|
| Element count | Two elements in one group, stated |
| Barrel size | 1.25 in |
| Camera thread | M42 × 0.75 mm, works as a T-adapter with a T-ring sold separately |
| Effect on eye relief | Not published by the maker. |
| Coatings | Broadband green-film multi-coated optical glass · blackened housing |
| Body | Aluminum, black anodized |
| Weight | Not published in the listing text · Amazon's item data gives 91 g (3.2 oz) |
| Amazon reference | B00WW0TC32 |
| EAN | 0635266457345 |
Two lenses cemented together into a single unit, the classic achromatic Barlow. It is the simplest correct design; triplets and apochromats improve color on fast telescopes.
The reflected color of an antireflection coating depends on its layers. A green reflection usually means a broadband multi-layer coating. SVBONY does not give the layer count.
Yes, with a T-ring for your camera brand screwed onto the M42 × 0.75 thread. The listing notes the T-ring is sold separately.
This model is listed on Amazon.com, at ≈ $18 at the last reading. Listed is not the same as in stock: availability changes daily, and the buy box shows the live price.
Details checked on November 7, 2026.
The cheapest way to double an existing 1.25-inch eyepiece set, with a camera thread included
Amazon reports what buyers took in the month before this page was last checked: at least 200.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Specifications: the manufacturer sheet for telescopes and observing optics and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
2x Barlow · 2 in barrel · ED glass · multi-coated · 2 in filter thread · 1.25 in adapter included
A 2-inch 2x Barlow in ED glass with multi-coated surfaces, a 2-inch filter thread and a 2-to-1.25-inch adapter, so both eyepiece sizes can be doubled.
Best for: A 2-inch focuser and wide-field 2-inch eyepieces that no 1.25-inch Barlow can take
≈ $63
3x Barlow · 1.25 in · apochromatic glass · M42 × 0.75 male thread · 1.25 in filter thread
A short 1.25-inch 3x Barlow in CNC-machined aluminum with apochromatic glass, multi-coated optics, a 1.25-inch filter thread and an M42 × 0.75 thread that takes a camera T-ring.
Best for: A short-focus telescope that needs planetary magnification, or a camera that cannot otherwise reach focus
≈ $24
2x Barlow · 1.25 in · apochromatic glass · M42 × 0.75 male thread · 1.25 in filter thread
A short 1.25-inch 2x Barlow in CNC-machined aluminum with apochromatic glass, multi-coating, a filter thread and an M42 × 0.75 thread for a camera T-ring.
Best for: A first Barlow that will also carry a camera, on a telescope that struggles to reach focus
≈ $19
