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Astromania 2-Inch Telescope Eyepiece Extension Tube Adapter - Optical Length 50mm - with Standand 2-Inch Filter Threads
Fits in 2 telescope focusers, and accepts 2 eyepieces or accessories. Threaded for use with standand 2-Inch astrophotography filters. Features two locking thumbscrews to secure any inserted astronomy accessory, with a brass compression insh to prevent the marring of your telescope accessories. Extension tube provides extra focuser back travel often needed for short-range terrestrial viewing through a telescope, or for astrophotographic applications. With this simple and useful device, you can extend the focal length of your telescope 50mm or a little more. The various models have focal lengths of 35mm, 50

Price is $31.00
Price: $30.99