A cartridge for an optical data storage disc includes a sheet metal sheath that is folded back on itself and a plastic insert that is inserted into the sheath. An opening is formed in the plastic insert for holding an optical data storage disc. The sheath includes two wall portions that are located on opposite sides of a bend area, where the sheet metal is folded. The two wall portions are attached to each other, preferably by spot-welding, to form a structurally stable sandwich that includes the plastic insert between the wall portions. The opening in the plastic insert becomes a cavity for holding the disc. A shutter opening is formed in one of the wall portions, and spindle openings are formed in both wall portions. A shutter covers the shutter opening when the cartridge is not operational to protect the disc. The disc is rotated by the spindle of an external disc drive which enters a central hole of the disc through the spindle openings. The use of sheet metal wall portions in conjunction with the plastic insert allows the cartridge to be made very thin. Used with an appropriate disc drive, the cartridge may be employed to provide a large amount of data to a CompactFlash or other type of card slot.