1.3″ W x 3.94″ H, duo LED light, wireless speaker, iron carabiner top, rechargeable Lithium Polymer battery, 37V, Capacity: 180 mAh, Input: 5V; Work Current: 40-60 mA; Sensitivity: 100±3dB at 2kHz; Frequency Response: 20Hz – 20 KHz; Transmission range: 10M (approx 30 feet); Wireless V 42, Playback time: approx 25 hours, depending on usage, minimum 2 hours, charging cable included, FCC approved.