Item Model: BRM-121 Folding 2.4G Wireless Mouse 1. Working Distance: 10 meters 2. Can be folded to save more space 3. Radio frequency: 2402MHz--2480 MHz 4. High resolution: 800DPI~1600DPI adjustable 5. Number of button: 3 keys 6. Power supply: 2¡ÁAAA battery 7. Button Life: more than 5000,000 times 8. Material: ABS 9. Support: Windows98/SE/ME/2000/XP/Vista, Mac OS 9.2 or above.