Bornd 2.4GHz Optical Wireless Mouse, Black (C190 BLACK) 2 years battery life with normal use Auto Sleep/Awake function for power saving Smart and ergonomic design for easy portability Holding the mouse, the position of your fingers feel comfortable with the concave design and plump back radian Gold-plated mini-receiver Excellent package design 2x AAA Alkaline Batteries (Not Included)