Solomark C-Mount to 1.25'' Adapter Ring - 1.25 Inch Barrel Adapter for Telescope Camcorder and Video Camera Allows C/CS mount cameras to be attached to any standard 1.25" eyepiece holder. The telescope adapter has a diameter of 1.25 inches for insertion in place of a 1.25 inch telescope eyepiece, allows the camera to be put into standard 1.25" eyepiece holders. The adapter is threaded for standard color filters and turned with internal stepping to combat stray light. For a 1.25" adapter to use C or CS mount CCTV type cameras with telescopes,threaded to accept standard 1.25" filters. For one high quality C-mount (male thread) to 1.25" (fit any telescope with 1.25" eyepiece tube) eyepiece convertor for telescopes.