Fixed Frequency: Dual UHF wirele microphone system, frequency: 520-560MHz. Adopt PLL frequency synthesis technology to provide trouble-free sound transmiion, minimum signal lo and maximum feedback rejection. Automatic frequency synchronization when power on, 100 feet - 150 feet wirele use distance, can support outdoor use. Strong anti-interference function: The karaoke wirele microphone is equipped with an automatic scanning function, which enables the system to search for the channel with the least interference to pair with the transmitter. The 2-antenna design increases the anti-interference ability and reduces the interference between each channel. G-MARK proprietary capsule: The dynamic microphone capsule of each microphone is developed and produced by G-MARK, and is printed with the G-MARK logo. The high-quality core effectively limits feedback and interference, picks up sound smoothly, and transmits easily. Provides clear, powerful, best authentic sound. Microphone Wirele is easy to use, plug and play, automatic pairing: Only plug the receiver into the MIC jack, but not the AUX jack. Then turn on the whole system and the receiver will automatically sync its frequency with the microphone. Adjustable volume control. Great for indoors, outdoors, karaoke, parties, churches, conferences, weddings, presentations, claes, openings, promotions, DJs, small live performances on stage, profeional engagements or religious events, etc. SPECIFICATIONS System parameters:Audio frequency response: 50Hz-18KHz Dynamic range: ge 80dBSystem distortion: le1%Signal to noise ratio: ge 60dBIdeal distance: 80m Operating temperature range: 5 -4.5 Carrier frequency range:500-580 MHzTRANSMITTERFrequency stability: plusmn 0.005%Carrier output power: le 30Mw Spurious radiation suppreion:>40dBModulation: FMMaximum modulation: plusmn 75KHzPickup mode: DynamicUse power: 1.5V Batterypower consumption: <30mAVolume: 37X 250mm (hand-held microphone)RECEIVERReceiver sensitivity: <2muVMirror suppreion:> 40dBTo increase: 50muSAudio output impedance: 600OmegaAudio output level: 0-0.5VUse power: AC110-240V 50 / 60HzPower consumption: 3W Volume: 420X210X45mm Package Included: 1 Wirele Receiver,2 UHF Wirele Handheld Microphones,1 1/4" Audio Cable,1 Power Adapter,2 Antennas,2 Roll Rings,1 x User Manual