Bornd 2.4GHz Optical Wireless Mouse, White (E200 WHITE) US Cypress RF Chipset 4 years battery life with normal use Auto Sleep/Awake function to save power Cellular technology, multipoint interconnection (many connection technologies compatible with Bornd wireless mice and keyboard) Press the Left and Right buttons at the same time for 3 seconds to adjust resolution between 1000 & 2000 DPI Excellent package design