Full-size, contoured ambidextrous design with soft rubber grips 2.4 GHz wireless technology. Unifying micro-receiver allows to connect up to 6 compatible mice and keyboards. Back/Forward buttons. Smooth and responsive laser tracking. 2-year battery life. Side-to-side scrolling and zoom. Programmable buttons. Requires 2 AA batteries (included). USB connectivity. Sold by each. Black.