Aluminum Alloy with ABS Plastic;Mini wireless speaker key chain; Power/Technology: Rechargeable Lithium-Ion battery; Input: 5V; Capacity: 140 mAh; Sensitivity: 100±3dB at 2kHz; Frequency Response: 20Hz - 20 KHz; Transmission Range: 10m (30 ft); Wireless V 42; Playback time: Approx 25 hours, depending on usage; Must be charged prior to first use Charge time varies by device Minimum 2 hours; Features LED indicator light, that shines red while charging (light goes off once charge is complete); Instructions and charging cable included; Product Size: 1.875" w x 2.125" h x 1.875" d; 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.;