Apple FileWare

They quickly ran into difficulties which precluded them from the Apple III, which continued to use the earlier Shugart design.

In a single-sided floppy drive, the disk head is opposed by a foam pressure pad.

In a normal double-sided floppy disk drive, the top and bottom heads are almost directly opposed.

The electrical interface is completely different from that of standard drives, though conceptually similar to that of the Disk II.

FileWare drives use 62.5 tracks per inch rather than the standard 48 or 96 TPI, and use high flux density (comparable to the later IBM 1.2MB format introduced with the PC/AT).

[6] The nature of models with "Twiggy" floppy drives being prototypes typically meant they were therefore often destroyed around the time of original production.

With the increased interest in old and rare Apple items, from the 2010s onwards, non-destroyed original models found in collections have often gone-on to sell for relatively high prices at auction.