The Concorde C-221M (Master) is an extremely rare third-party floppy disk drive, released by the Canadian company Concorde Peripherals in the mid-1980s. It is a standalone drive consisting of a high-quality floppy disk drive, a power supply, and disk operating system software. In addition to high accuracy and fast data access, the C-221M can support up to three Concorde C-221S slave drives.

The drive was fully compatible with both single-density (90 KB) and double-density (180 KB) modes. Internally, it used a high-quality 5.25-inch half-height drive, making the device more compact and modern compared to the bulky Atari 810.

One of its key features was a built-in ROM operating system, or advanced disk utility, that allowed disk copying and file management without loading a separate DOS from a floppy disk.