1. Keynote. - especially designed for notebook users - ultra slim: 5mm in thickness - easy to carry 2. Features: 1) optical navigation based upon patented optics 2) two button and touch scroll wheel 3) interface: USB (1. 1~2. 0) or combo 4) windows XP / 98 / 2000 / nt compatible 5) size: 94mm*53mm*5mm 6) resolution: 800 cpi 7) available to change color 8) changeable skin by buyer's favor 3. Certification - CE, FCC, rohs, MIC