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ZWO M42 to M42 Extension Tube - 21mm - T2-EXT-21

ZWO M42 to M42 Extension Tube - 21mm - T2-EXT-21 - Main image
$10.8 $18 In stock

Category: Telescope Accessories

ZWO 21mm M42 to M42 Extension

Made of black anodized machined aluminum, this ZWO M42 to M42 Extension Tube is 21mm in length and is used to reach your imaging system's proper back focus.

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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 (4.6 / 5 · 5 reviews)

Benjamin ★★★★★

Finally got the spacing right for my imaging train with this 21mm tube. The black anodized finish matches perfectly with my other gear and feels solid.

Harper G. ★★★★★

The threading is buttery smooth and the black anodized finish matches my other gear perfectly, which made racking in that last 21mm of back focus a total non-issue. It's exactly the right depth for my setup, and the aluminum body feels solid enough to last forever.

Ava E. ★★★★★

Finally got the back focus dialed in for my imaging train with this 21mm extension. The black anodized finish matches perfectly with my other gear and fits snugly without any play.