The Pro Fit Mid-Size Wireless Mouse is built to deliver with a nano receiver that operates 2.4 GHz to reduce interference in crowded office environments. The small receiver can be left in the computer or stored in the Pro Fit's built-in receiver storage compartment. The mouse is large enough to feel just right in the hand, yet small enough to pack easily while out and about. Featuring a high-definition optical sensor for precise, responsive cursor control on a variety of surfaces, operating for up to 12 months on 2 AAA batteries (included.) Supplied in blue.