Specifications: 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. Item Name: Pen Mouse Material: ABS Operating Frequency: 2402MHz - 2480MHz Transmission Distance: >10M, 360 Degrees Resolutions Adjustable: 500/1000cpi Tracing System: Optical Operating Current: 15mA 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 (Not Included) System Requirements: for Windows98/XP/Vista/Windows7, for Tablet PC, for Mac OS X, for Linux Features: Wireless, Ergonomic Design, Pen Shape, Easy to Use Size: 140mm x 20mm x 15mm/5.51" x 0.79" x 0.59" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Pen Mouse 1 x 2.4G Receiver