This USB 2.0 switch allows 2-4 PCs to share one peripheral such as a printer. The switch requires no external power sources as it operates off the USB bus power. This device is compatible with Max OSX and Windows: 98, Me,2K, XP and 2003. It has 4 USB Type-B female ports to connect to the PCs and one Type-A female port to connect to the peripheral. Included is one USB Type-A male to Type-B male cable. This device can be operated by pressing one of the buttons on the unit's top to select the appropriate computer or a hotkey can be programmed. It comes with a installation CD for this purpose.