Agfa Karat 3.5 camera was produced in Germany from 1938 to 1941. Karat 36 designed for standard 35mm cassettes, this unit uses the unique "karat cassettes" which transport film from a loaded cassette to an empty take up one. The sprocket "teeth" aid in the transport system as do two unique folding flaps that hold the emulsion flat on the film tracks. The pressure plate also does its part to ensure flatness. The bellows are hidden behind the lens mount plate. A button on the top body plate unlocks them to a fully extended state, and a thumb lever at 3 o'clock enables the user to retract the bellows in a closed position. Also on the top plate, one will find the tunnel like viewfinder, the advance knob, film counter and the shutter release button. The lens is a Agfa Solinar 3.5 50mm, 2 elements cemented together form the rear group, and the front two elements also cemented together form the front lens group. The focusing is achieved by rotating the front group to the desired distance. The shutter and aperture blades reside between the front and rear lens groups. The shutter is a Compur Rapid rim-set type with speeds from 1 second to 1/500 of a second plus B. It requires manual cocking prior to release.