2.4GHz wireless connection, up to 10m operation distance (depend on environment). If there is no 2.4GHz signal, it will automatically power off to save power. Ergonomic pen shape design, fits comfortably on your hand. With low voltage alarm function, reminds you to replace battery in time. Real plug and play, no extra driver needed. Operating Frequency: 2402MHz - 2480MHz Resolutions Adjustable: 500 / 1000cpi Tracing System: Optical Operating Current: 14mA Button Numbers: 4 Buttons Rated Work Voltage: 3V Rated Work Current: 15mA Channel: 16 with Automatic Frequency Hopping Power Supply: 1 x 1.5V AAA Battery System Requirements: for Windows98/XP/Vista/Windows7, for Tablet PC, for Mac OS X, for Linux Wireless, Ergonomic Design, Pen Shape, Easy to Use Delivery quantity: 1pc Package content: only the above package content, excluding other products. No battery Size: 14 * 2 * 1.5cm (Warm prompt: the size is measured manually, please allow 1-2 cm measurement error) Color: blue (Due to different displays and lighting effects, the actual color of the product may be slightly different from the color shown in the picture.)