... button and Middle button) & Trackball & 3mW Laser Pointer. Wireless intelligent connection, with wireless operation distance up to 10 meters. Ergonomic layout: QWERTY ... entertainment, conference, lecture, presentation etc. Specification: device typeMini 2.4G wireless key boardoperating distance10mworking voltage3.3vworking current<10mAcharging voltage4.2-5 ...