Includes MicroPDP-11/73 CPU, Choose one. -C2/-D2 recommended for US. 1-Mbyte (MSV11-QA) memory, asynchronous console serial line on the CPU module, BC22D-10 serial-line cable, BA23A-AF pedestal/tabletop enclosure, and a US 120-V power cord. Does not include diagnostics or user documentation - see Step 5 to order separately. Same as 173QY-C2 except 240 V and does not include a US 240-V power cord - see Step 2 to order separately Same as 173QY-C2 except includes a BA23A-AR rackmount enclosure instead of a B Compaq Professional XP1000 enclosure Same as Compaq Professional XP1000 -C3 except includes a BA23A-AR rackmount enclosure instead of a BA23A-AF enclosure Includes MicroPDP-11/73 CPU, 2-Mbyte (Compaq Professional XP1000 -QB) memory, asynchronous console serial line on the CPU module, BC22D-10 serial-line cable, BA23A-AF pedestal/tabletop enclosure, and a US 120-V power cord. Does not include diagnostics or user documentation - see Step 5 to order separately. Same as Compaq Professional XP1000 -D2 except 240 V and does not include a US 240-V power cord - see Step 2 to order separately Same as Compaq Professional XP1000 -D2 except includes a BA23A-AR rackmount enclosure instead of a BA23A-AF enclosure 173QZ D3 Same as 173QY-D3 - except includes a Compaq Professional XP1000-AR rackmount enclosure instead of a Compaq Professional XP1000-AF enclosure