Video of RWM90U: Unboxing Video of RWM90U: Includes : 4 wireless handheld microphones 1 receiver unit User manual Batteries Power adapter Features: Rockville RWM90U UHF Quad Wireless Microphone High performance wireless handheld microphone system Includes transmitter with four high sensitivity, unidirectional, wireless, handheld cardioid microphones Color coded microphones Featuring a dual filter design to limit feedback and interference Ultra signal stability eliminates unwanted distortion Professional receiver with multifunction color displays shows frequency, signal synch, and audio input Transmitter automatically links to receiver for ease of use Individual microphone volume controls Receiver has a rugged metal housing Comfortable ergonomic composite microphone construction Low power consumption for longer battery life ??Available in 4 Frequencies: A B C D 1 467.9 473.9 479.9 485.9 2 469.1 475.1 481.1 487.1 3 470.3 476.3 482.3 488.3 4 471.5 477.5 483.5 489.5 5 472.7 478.7 484.7 490.7 System : Operating Range: 300´ – 400´(indoor), 250´ – 350´(outdoor) Channel: Four Channel Frequency Range: 467MHz – 490MHz Frequency Stability: ±0.005% Modulation Mode: UHF Frequency Response: 50Hz – 15KHz (±3 dB) Dynamic Range: 105dB S/N: 100dB T.H.D: < 0.5% (1KHz) Audio Output Jack: XLR balanced & 1/4 mixed Power Voltage: AC110V/ 220V – 50/60Hz 110V/220V Volt Switchable Operating Temperature: 3°F – 130°F Mic Battery Operating Time: up to 10 hours Oscillation mode: Quartz Crystal RF Output Power: 10mW Output Level: 0 – 300mV Owner’s Manual ??