Imprint Method: Pad Print, Product Color: Silver - This wireless Aluminum case cylinder wireless speaker with steel mesh cover and no-slip bottom. Rechargeable Lithium Polymer battery: 3.7V, Capacity: 350 mAh; Input: DC 5V; Output/Power: 3W; Aux in: 3.5 mm audio jack; Rated Impedance: 4 Ohm; Speaker: 1.6 inches; Frequency response: 90-20KHz; SNR: = 85d; Sensitivity: 80db plus or minus 2db; Distortion: = 0.3%; Transmission range: 10M (30 feet); Bluetooth 4.0. Connects to your mobile device using wireless technology or through the 3.5 mm audio cable (not provided). Push button to answer phone calls. Speak hands-free into built-in microphone. Also play MP3 files though a USB flash drive or TF card. Instructions included. CE and FCC approved. Playback time: 2-4 hours.