To distinguish optical disk cartridges stored inside a magazine by forming a window part with a transparent member, on the back face of the magazine.

Optical disk cartridges are arranged in parallel in a slit formed in a magazine 11. When the optical disc cartridges are used on the recording/ reproducing occasion, generally, the cartridges are loaded in an optical disk automatic changer apparatus to correspond to a recording/reproducing apparatus set in the apparatus. In the optical disc automatic changer, an opened window part is provided on the back face of the magazine, through which rear parts of the stored cartridges can be seen. A transparent member is fitted at the window part. Therefore, if the optical disk cartridge have label displays at the rear parts thereof, the cartridges can be distinguished through the window part even when the cartridges are stored in the magazine.