One unusual feature of the System One is that it had a metal enclosure rather than plastic. Perhaps this was a convenient way to shield for RFI, which the government was cracking down on at the time.
Extra Computer System One (June 1983, Apple II-class desktop)
Original Retail Price: $795
Base Configuration: Z80A and 6502 CPUs, CP/M 2.2 and AppleDOS, seven Apple-compatible slots, 64K RAM, 24K ROM, NTSC and RF video ports, integral keyboard/keypad, game port, Perfect Writer and Perfect Calc, CP/M manuals
Video: 80-column text, 280 x 192 graphics