The 2" Zero-Profile Prime Focus Camera Adapter couples your camera to a telescope for prime-focus astrophotography. The Zero-profile design provides closest possible in-travel for cameras in any 2" telescope focuser. It threads directly into the T-ring (sold separately) for your single lens reflex/digital single lens reflex (SLR/DSLR) camera body and is also threaded for 2" telescope filters. The Zero Profile Camera adapter fits 2" telescope focusers on refractor and reflector telescopes.