Rack & Pinion 2" Focuser Extension Tubes

Rack & Pinion 2" Focuser Extension Tubes - View 3

Rack & Pinion 2" Focuser Extension Tubes - View 4

Rack & Pinion 2" Focuser Extension Tubes - View 5

Rack & Pinion 2" Focuser Extension Tubes - View 6

$17.99 ~~$29.99~~ In stock

Category: Focusing

Description

Explore Scientific Rack and Pinion Focuser Extension Tubes add 0.5" or 1.5" to our 2-inch Rack and Pinion focusers on our ED APO telescopes.

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When it ships

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

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

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If you need a refund

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Delivery costs

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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Returning an item

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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 (4.8 / 5 · 5 reviews)

Joshua ★★★★★ Oct 21, 2026

Adding the 1.5" extension tube gave me just the right amount of back focus for my camera setup, and the rack-and-pinion mechanism feels smooth and precise.

Andrew ★★★★★ Oct 20, 2026

The 0.5" tube was a perfect fit for dialing in the focus on my triplet, and the rack and pinion mechanism feels precise and solid. I've had zero slipping since install.

Sofia Z. ★★★★★ Oct 19, 2026

The 1.5" extension tube let me finally reach focus with my binoviewer—threads are smooth and tight. No image shift or wobble when racking in and out. Exactly what I needed for my 2" focuser.