YamaYahoo&reg; BM50 0.6" Bluetooth Headset Phone w/ Dialer / Earphone - White The smallest size phone in the world.Dimensions 2.95 in x 0.91 in x 0.98 in (7.5 cm x 2.3 cm x 2.5 cm) Used as a bluetooh earphone for making a call ,listening to music ,free your hands from your cell phone and tabllet pc ect. Talk Time 3Hour ,Standby Time 120Hour Battery Type 300mAh Li-ion battery Frequency 850/900/1800/1900MHz