Another beauty. Coated, multi element lens assemblies, mounted. Front element clear diameter is 100mm and rear element clear diameter is 77mm. Unfortunately our lens analyzer can’t measure its negative focal length because of it’s size. Barrel is 108mm diameter by 41mm long and front flange is 118mm diameter. We don’t have a clue what these were made for but clearly a very expensive optic. Weighs 2 pounds. Only have a few.