Threaded Extension Tubes for 2.4" Focusers

Threaded Extension Tubes for 2.4" Focusers - View 3

Threaded Extension Tubes for 2.4" Focusers - View 4

Threaded Extension Tubes for 2.4" Focusers - View 5

Threaded Extension Tubes for 2.4" Focusers - View 6

$29.25 ~~$39~~ In stock

Category: Astrophotography Accessories

Description

Focuser extensions of various lengths are often used to create the necessary distance for proper spacing of field lenses to imager; the required distance will vary depending on camera specifications. All are black anodized aluminum with anti-reflection threads for maximum contrast.

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (5.0 / 5 · 5 reviews)

Abigail ★★★★★ Oct 17, 2026

Getting the right spacing for my camera has always been a headache, but these extension tubes clicked together perfectly and let me dial in the exact backfocus I needed. The set of multiple lengths saved me from buying a bunch of separate adapters.

Ellie ★★★★★ Oct 13, 2026

I was fighting backfocus on my ASI294 for weeks until I added this extension, and now the field lens spacing is dead on. The threads are machined well enough that there's zero wobble or light leak at the connection. Wish I'd grabbed one of these sooner instead of shimming with spacers.

Lucy A. ★★★★★ Oct 12, 2026

Threads mated cleanly to my focuser with zero wobble. I stacked two lengths to hit the backfocus on my 294MC and stars stayed pinpoint to the corners. Nice having the exact spacing without a pile of spacers.