Our Shipping conditions: Attention: The goods will be shipped from UK Delivery time: 2 to 4 working days Support 60 days return policy Reply within 24 hours Specification: Maximum sound output: 118+/- 4dB Sound gain: >= 32dB+/- 2dB Total harmonic distortion: <= 7% Frequency: 300-3800MHz Input noise: <=32dB Voltage: DC 3.7V Current: <=2mA Charging time: 3 hours Normal working time: 45 hours Colour: silver Features: .