A4Tech J90 2-FIRE RGB Animation Gaming Mouse Sensor: PixArt PMW3325 Gaming Engine ,Resolution: 100~5,000 CPI, Image Processing: 3.61M pixels/sec,Frame Speed: Adjustable,Acceleration: 20 g,Tracking Speed: 100 ips,Response Report Rate: 125~1,000 Hz/sec, Key Response: 1 ms, DURABILITY Micro-Switch: Over 20 Million Clicks ( Left / Right Button ), Wheel: 500,000 Scrolls,Metal X'Glide Armor Boot: Over 300 Kms.