Cloud Break Optics

M54-M48 extender 21mm

M54-M48 extender 21mm - Main image
$17.25 $25 In stock

Category: Astrophotography Accessories

The ZWO M54-M48 Extender is a 21mm adapter designed to connect M54 threads to M48 threads in an astrophotography imaging train. It is part of ZWO's line of threaded accessories for building and adjusting optical spacing.

  • Brand: ZWO
  • Product type: M54-M48 extender
  • Extension length: 21mm
  • Thread compatibility: M54 to M48
  • SKU: ZWO-M54-M48-21

This extender provides a threaded M54-to-M48 connection with a 21mm extension, useful when configuring spacing between compatible astrophotography components.

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Customer Reviews (4.8 / 5 · 5 reviews)

Joshua ★★★★★

Finally got the spacing right on my imaging train—this adapter threaded on smoothly without any wobble. The 21mm extension fits perfectly between my reducer and camera.

Edward J. ★★★★★

I needed exactly 21mm of spacing for my filter wheel to reach focus, and this extender did the trick without adding any tilt. The M54 to M48 threading engaged smoothly and held everything rigid in the imaging train.

Jacob Z. ★★★★★

The threads are machined perfectly smooth—no wobble or binding when screwing it into my filter wheel. This 21mm extender gave me just the right back focus for my setup, and the anodized finish blends right in.