If used for four computers to share a parallel printer, it is plug and play with no software to install. If used for one computer to access four printers, the bundled software provides software-controlled switching between printers & broadcast capability. Supports all parallel centronics printers except inkjet and some high speed laser printers. Optional TR011-AT power adaptor maybe needed when used with some notebooks. Works with DOS, Windows 3.1x, 98/98SE, ME, 2000 systems. Recommended Cables: CC405D DB25 Male to Male. (Connectors: 5 DB25 Female)