The Tangelo Soho Wireless Mouse features an ergonomic design with multiple programmable multi-function buttons: two thumb buttons, a centrally located button below the scroll wheel, and a click-button scroll wheel. The optical sensor has adjustable DPI, meaning the user is able to fine-tune cursor sensitivity. Product runs on a 2.4GHZ wireless connection. Wireless dongle is included and attaches to underside of the Soho for simple and convenient storage. 2x AAA batteries included.