Extension tubes for ESATTO 3"

$102 ~~$150~~ In stock

Overview

When installing ESATTO 3" in a telescope with a long travel focuser (such as those usually found on refractors), it is necessary to take into account the lower travel of ESATTO 3" since it's a micrometric focuser. For this reason we have designed these 40mm and 65mm extensions that can be installed between ESATTO 3" and the telescope tube. A precise dovetail coupling system with 3 screws set at 120° allows you to manually rotate the focuser.

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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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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 (4.4 / 5 · 5 reviews)

Matthew ★★★★★ Oct 21, 2026

Installing these tubes was straightforward, and the threads are cut so smoothly that everything seated perfectly on the first try. The length options covered the back focus gap I was worried about, no wobble at all.

Sophia ★★★★★ Oct 20, 2026

The solid aluminum construction gives these extension tubes a reassuringly precise feel when threading onto my focuser. I was worried about extra weight, but they're actually lighter than I expected for the thickness. My imaging train now sits at the perfect distance without any flexure.

Stella ★★★★★ Oct 19, 2026

Finally, my focuser has enough back focus to reach focus with this setup. The threading is very smooth and mates perfectly with the ESATTO 3".