This is the standard "A12" type 120 film magazine for the Hasselblad camera system.
NOTE: Hasselblad makes three basic types of film magazines: "A", "E", "E-CC". They are interchangeable with all Hasselblad cameras. The "A" type is the standard non-electronic magazine in the Hasselblad line. The "E" type is specifically designed for the 200 Series and is equipped with a film speed programming dial and electronic databus connections which transfer the film speed to the camera's metering system. It can be used with the 500 Series cameras but only works mechanically. The "E-CC" magazine is specific to the 205FCC model and is not only equipped with the same "E" features, but also has a contrast control dial ("CC") which is used in conjunction with Zone System black and white photography.
