3M™ Ergonomic Mouse - EM500GPS - Small - Grapbhite (Black) Clinically proven to reduce the muscle strain and discomfort associated with carpal tunnel syndrome and repetitive stress injury. Vertical grip reduces pressure on the wrist's median nerve. Records optically for smoother, more accurate mousing. Optical sensor has no moving parts ot wear out or to clean. Graphite colour. Both USB and PS2 Compatible. For Right Hand Use Characteristics Color Graphite For Use With IBM Compatible PC Material Plastic Size Small/Meduim Trademark 3M™ Trademark Name 1 3M Trademark Name 1 with suffix 3M™