Mouse Wireless HP X7800 “Wireless 2.4 GHz technology. Ergonomic design, comfortable hand touch,easy Built in sensitive optical sensor. Mini nano receiver is slot in side mouse. On/Off power switch to extend battery life. Automatic off function to save battery energy. Up to 10 meters operation distance. Key switch life more than 5 million times. Low power consumption. Supports Windows XP/ME/NT/ Vista and Mac or higher version. 1 AAA Alkaline battery.