p The USB421HS 4 to 1 USB Switch Box allows for a USB 2.0 device to be shared with up to 4 different computer systems, without having to disconnect and reconnect the cabling everytime. Push button controls makes switching between computers quick and easy, with additional keyboard hot key switching and Windows based software also available. p p With no external power adapter required, and with its compact design, the USB 2.0 data switch takes up very little space and is easily portable. Backed by a StarTech.com 2 year warranty and free lifetime technical support. p