Wireless surface microphone set (with transmitter and receiver) - Frequency range: 2.4 GHZ - Frequency response: 20 Hz - 20 KHz (+- 3 dB) - Output impedance: 2200 ohms - Pairing method: Automatic - Microphone type: Condenser - Microphone directivity: Omnidirectional - Microphone dimensions: 6 x 2.7 mm (0.2 x 0.1") - Microphone sensitivity: - 42 dB (+- 2dB) - Signal to noise ration: > 63 dB - Power supply: Rechargeable lithium battery - Power consumption: < 70 mA at 0 dBm - Operating voltage: 2.0 - 10 V DC - Operational distance: 25 metres (82 feet) - Operational time: Up to 6 hours - Included: 6.35 mm (1/4") audio adapter plug, double charger cord and replacement stickers