Model: FMK-04 Battery: 180mAh, 2mA/3.7V Material: Aluminum alloy+ plastic Chips: Broadcom 3.0 Total Keys: 81 Charging time: 2 hours Working time: 80 hours Standby time: 2 months Unit size: 35.8*10*0.9cm Fold size: 17.8*10*1.8cm Net weight: 208g Color: Space gray