Acrylic knit beanie with wireless headphones Power/Technology: rechargeable Lithium Polymer battery: 3.7V/200 mAh; Input: 5V; Output Power: 2W x 2; Work current: 200 mA in charging; Frequency response: 20Hz-20 kHz; Transmission range: 10m (32 feet); Wireless V 4.2. Playback time: approx. 3 to 3.5 hrs depending on usage. Must be charged prior to first use. Charge time varies by device. Instructions and charging cable included. LED indicator lights