2" 40mm Eyepiece Barrel Extension

Extension focal length: 40mm. Total length: 70mm. Extension tube provides extra focuser "back travel" often needed for short-range terrestrial viewing through a telescope, or for astrophotographic applications Fits in 2" telescope focusers, and accepts 2" eyepieces or accessories. Threaded for use with standard 2-Inch astrophotography filters Features a locking thumbscrew to secure any inserted astronomy accessory, with a brass compression ring to prevent the marring of your telescope accessories With a brass compression ring to prevent the marring of your telescope accessories Machined of high quality aluminum and anodized black, durable for long time use