GSO 25mm Extension Tube for 6" and 8" RC Telescopes with M90x1 Thread # FF083

Our #: PAAR-GS-FF083
Mfg #: FF083
Our Price: $26.95
Free shipping for this item in the US
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Out of Stock
Availability: Expected mid-April

Quick Overview

  • GSO 25mm-long x 90mm extension ring for 8” RC telescopes
  • Ideal for adjusting back focus to minimize extension of focuser tube
  • Made of black-anodized aluminum with anti-reflection threading

Product Details

GSO 25mm Extension Tube for 6" and 8" RC Telescopes with M90x1 Thread # FF083.

This adapter features M90x1 male threads on one side and M90x1 female threads on the other side, and provides 25mm of additional spacing. You can use this to move the focuser farther away from the rear cell of select GSO Ritchey-Chretien (RC) telescopes if you need to adjust back-focus for your imaging setup.

Most GSO RC telescopes already come with some extension rings (see individual telescope descriptions for details of included accessories), but you can use this spacer ring if you need additional spacing for your specific setup. It is also preferable to use a spacer like this instead of racking the telescope focuser out in order to minimize flexing, especially if you use heavy cameras or imaging accessories.

Precision machined from black anodized aluminum. Painted flat black and features anti-reflection grooves on the inside. Made in Taiwan.

Specifications:

  • Total length = 34mm (1.34")
  • Length of M90 male thread (including unthreaded undercut) = 8.6mm (0.34")
  • Length of M90 female thread (including unthreaded undercut) =10mm (0.40")
  • Extension provide = 25mm (0.98")
  • Outside diameter = 94mm (3.70")
  • Inside diameter (clear aperture) = 78mm (3.08")
  • Weight = 4.5oz (128g)

Other Information

  • Country of Manufacture: Taiwan