Specifications: Oscillator Type: PLL synthesized control oscillator RF Output Power: 10mW Channels: 48 Frequency Response: 40Hz-18kHz Distortion: 0.5% or less Reference Audio Input Level: -60dBV Operation Range: 100m/ 300"(without obstacle) Power Supply: 2 * AA batteries Item Size: 10.3 * 6.2 * 2.2cm / 4.1 * 2.4 * 0.9in Item Weight: 82g / 2.9oz(transmitter); 92g/ 3.2oz(receiver) Package Size: 23.5 * 19 * 5cm / 9.3 * 7.5 * 2in Package Weight: 640g / 1.4lbs