Schneider-Kreuznach Repro Claron 55mm f/8 (M25, M39, M42 with adapters) The lens has originally M25x0.5 screw mount! I give you an additional M25x0.5 / M39x1 adapter, and an M39/M42 adapter ring as well! This way you can use it immediately either on a Leica camera (or adapter), or on an M42 camera (or adapter). This is a fully symmetric Double Anastigmat Dialyte (Dialyt) lens construction with 4 separate elements, great UV transmission, cca zero aberrations, image distortions, sharp from corner to corner even wide open! The lens has 53mm FFD (Flange Focus Distance). So, you can use it even on a DSLR! Inspecting with strong flashlight the front glass has a slight fog, otherwise, with naked eye it is perfect! BTW, the lens is in like new condition both outside and inside, the aperture ring moves easily, the blades are clean and shiny, without dusts inside, etc! I shot a test pic with it (with a little added contrast). The last pic! It is sharp from corner to corner wide open, with a very clear, distortion- and aberration-free image!