This is a Yashica Mat LM, a twin lens reflex camera (TLR). The top lens is used for focusing and the bottom lens takes the photo. When you focus it, the front plate of the camera, holding both lenses, moves in and out. You look into a big ground glass viewfinder in the top and stop when the image is in focus. The LM stands for light meter. This one is an extreme rarity, because the selenium cell light meter still works (although I am not sure about the accuracy of a very old meter powered by a selenium cell -- they usually have a ten year lifespan and this is from the 60s). It has a very sharp Yashinon lens and a Copal SV shutter. The shutter speeds are from 1 to 1/500th second plus B. The f/stops go from f/3.5 to f/32. Everything works as it is supposed to, including the self-timer. It has been releathered with something called "Griptac," a textured vulcanized rubber camera covering that is supposed to give you a better grip. Originally, it came with a vinyl covering. The original covering was brittle and had broken off in one corner of the front plate.