This is a modified Chaika camera for taking half-frame photos with an elmar 35mm lens. It's often thought that L39 mount lenses will fit, but simply matching the flange back isn't enough. The inside of the mount has been shaved down and light-sealing tape applied. The flash sync cord was also removed as it was in the way, so the flash sync terminal is unusable. Of course, collapsible lenses won't fit. Well, they *will* fit if extended, but you can't collapse them. Lenses with a similar thickness to the elmar 35mm (the rear part of the mount) can be attached. The frame counter works, but it's not very precise. It moves via gears when the shutter is charged, but it only has a rubber brake, so the count might shift if you give it a jolt. Pulling the rewind dial on the bottom loosens the counter's brake and resets it to 0. The viewfinder is clear, like looking straight through. If you're feeling adventurous and want to try taking half-frame photos with an elmar or other L39 mount lenses, I'm looking forward to hearing from you. Thank you.