This adapter make you attach your video camera with a 'C' or 'CS' thread to your telescope for prime focus photography. C-threads are commonly used in most consumer video cameras whereas the CS thread is mostly used in security cameras. The camera must have a standard removable C-mount lens, which is a 1" diameter thread. Will not work on video cameras with a fixed lenses or bayonet mount.
Useway: attach the camera to the C-thread of this adapter. Then slide the 1.25" barrel into your 1.25" telescope focuser and you are ready to shoot. Internally grooved to reduce stray light reflection for maximum contrast.