The Super-Switch wireless interface works with all special needs switch access software. Its 5" diameter is a great large target for those who need it. The 3 switch inputs allow you to mimic mouse clicks and with the installation of the accompanying software, you can configure each button to be any keystroke or mouse-button event. PC and MAC compatible. Requires USB port. Size: 5" Diameter and 1¼"H. Requires 2 AAA Batteries.