MP3 Sunglasses/BLUETOOTH SUNGLASSES 1) Complies with Bluetooth 1.2 standard (Bluetooth) 2) Transmitted power: Class 2 3) Wireless connection range: 10m 4) Operation frequency range: 2.402GHz - 80GHz 5) Sound output mode: Double track 6) Talking time: 4 hours 7) Standby time: 120 hours 8) Digital formats supported: MP3/WMA (MP3 player) 9) Signal-to-noise ratio: 87.2dB 10) External hard drive function: Yes 11) Audio additional features: Auto-power off 12) Earphones type: Binaural MFR estimated 13) Battery life: 5 hours 14) Charging time: 3 hours 15) Battery tape/capacity: Built-in lithium-ion polymer/3.7V, 150mAh 16) Maximum input power rating: 5VDC, 150mA 17) Voice output power: 55mW 18) Frequency: 20Hz - 20KHz 19) Earphone impedance: 16Ω x 2 20) Memory capacity: 64MB - 1GB Inner packing: Blister card Standard English paper box with USB cable, CD and instruction manual Small gift box dimensions: 10 x 8.0 x 18cm Outer packing: 50PCS/carton Carton dimensions: 44 x 39 x 55cm G. W.: 15.50kg