Aluminum alloy; Duo LED light and wireless speaker; Iron carabiner at top for easy on the go carry-along; Power/Technology: 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); WirelessV 42; Playback time: approx 25 hours, depending on usage; Must be charged prior to first use Charge time varies by device Minimum 2 hours; Instructions and charging cable included; FCC Approved; Product Size: 1.3 w x 3.94 h; Shipping available to contiguous U.S. addresses and Canada via Ground only.  Cannot ship via Air, Internationally or to Alaska, Hawaii, Puerto Rico and any other small U.S. island territory.