Bargz Ergonomic Design -Built in Memory - Plug and Play - 3222 2.4G Wireless Optical Mouse - Yellow Color Perfect in size, design, and control. 4GHz digital wireless transmission to provide furthest reach 10 meters from the operation 16 wireless working channels, automatic frequency-hopping Nano very fine receiver, plug&play, without connecting the Code of intelligent technology Mouse built-in memory, the replacement of the batteries do not have to recode