Allows attachment of a DSLR or Mirrorless camera equipped with a T-ring to a telescope Useful for either prime-focus or eyepiece-projection astrophotography with refractors or reflector telescopes Accepts 1.25" eyepiece inside for eyepiece projection astrophotography Slides into 1.25" telescope focuser; has T-threads for attachment of camera body Requires T-ring (sold separately) for your particular brand of camera