SVBONY SV157 1.25″ Extension Tube

Product Overview

The SVBONY SV157 is a 1.25″ extension tube that adds 56 mm of length between your focuser or diagonal and an eyepiece or 1.25″ camera. It is all-metal aluminium alloy, ø39 x 56 mm, with a fully threaded interior to reduce reflected light, and its end is threaded to take a standard 1.25″ filter. This listing is the 56 mm length (item W9118A).

Who It's For

This is a good match if an eyepiece, camera or accessory on your telescope cannot travel far enough outward to reach focus and needs extra length in the 1.25″ train.

Key Features & Design

• 56 mm of extension: moves the focal plane position outward to bring an eyepiece or camera to focus.
• 1.25″ barrel and holder.
• Filter thread at the end: takes standard 1.25″ filters.
• Fully threaded interior: reduces internal reflections.
• CNC-machined aluminium alloy: all-metal, black.

Recommended Uses

• Reaching focus with eyepieces or 1.25″ cameras on telescopes with limited outward travel.
• Spacing in a 1.25″ imaging or visual train.

Compatibility and Accessory Notes

• Fits: 1.25″ focusers and diagonals; accepts 1.25″ eyepieces and nosepieces.
• Other length: SVBONY also makes the SV157 in 70 mm (W9118B); ask us if you need that length.

Good to Know Before You Order

• Moves focus outward only: an extension tube helps when you run out of outward travel; if your eyepiece needs to come inward, it adds to the problem rather than fixing it.
• Length: this listing is 56 mm.

Frequently Asked Questions

Is it difficult to set up?

No. Insert it into the focuser like an eyepiece, then put the eyepiece or camera into the tube.

How do I know if I need one?

If you rack the focuser all the way out and the image still is not sharp, extra length is what you need. Send us your telescope and eyepiece and we will check the length for you.

Can I add a filter?

Yes. The end is threaded for standard 1.25″ filters.

Bottom Line

In short: a 56 mm all-metal 1.25″ extension tube with a threaded, reflection-reducing interior for bringing eyepieces and cameras to focus.