MX-220 3D Combo Optical Mouse [MS-22-0S-PC] is the state-of-art professional Slim Size Optical Mouse. With the Ergonomic design, MX-220 is designed to be comfortable and specially fit for your hand position and avoid fatigue after use it for long period. Tranquil-design wheel for scrolling four contact points to reduce resistance and ensure excellent mobility and easy to control on different surfaces.