The Super-Transmission-Coated with 2-element lens system was designed and produced by William Optics, the inner flattener lenses can be set at the optimum 66mm-86mm back focus distance (Distance from flattener lens to film or CCD plane)
• Rotating T-ring thread for any 35mm camera. The T-ring adapter is provided with a lock screw and extra lock retaining screws.
• Will accept any standard T-ring for your camera.
• Inserts directly into 2" focuser.
Power : 0.75x ~ 0.8x