Perman Mini 2.4GHz Wireless Optical Mouse Mice with USB Receiver for Computer PC Laptop Notebook Black Mouse type: Wireless Optical Mouse. Optical Resolution: 2000 (dpi) Dimensions (L / B / H): 8.5 x 5.3 x 2.7cm. Interface: USB. Mini adapter Plug and play. With 3 Keys, including Scroll Wheel, Page Forward and Page Backward buttons for easy Internet Surfing. Power switch for save power. Power Supply: 1 x AAA Battery (Not included) Wireless transmission, the longest sensing distance up to 10-15 meters. Portable and weight light, very convenient to carry and store.