Frequency Adjustable: Dual UHF wirele microphone system with selectable frequency: 520-580MHz. Employs PLL frequency synthesized technology to provide hale-free sound transmiion, minimum dropouts, and maximum feedback rejection. Smooth and quick IR synchronization. Long range operation of 200ft 250ft line of sight Anti-interference feature: Karaoke wirele microphone equips with auto scan function, which enables system to search for the least interference channel to pair up with transmitters. 2 antennas design increases anti-interference ability and decreases interference between each channel. Microphone Easy to Use, Plug and Play, Automatic Pairing: Plug the receiver into the MIC jack Only , but not into the AUX jack. Then turn on the entire system, the receiver will automatically synchronize its frequency with the microphones. Adjustable Volume Control. Perfect for indoor, outdoor, karaoke, party, church, meeting, wedding, speech, cla, opening ceremony, promotion, DJ, small live performance on stage, profeional engagement or religious event, etc. G320AM frequency adjusted method: 1. Click the of the receiver, and then click .2. Select the channel, pre again, there will be a drop of sound.3. Align the circular hole of the wirele microphone with the IR of the main unit. After the sound is reduced, if the frequency of the microphone is the same as the main unit, it means that the frequency is corrected.4. When the frequency displayed in the receiver is the same as the handheld screen, the frequency adjustment is complete. G-MARK Proprietary Capsule: The dynamic microphone's capsule of each microphone is developed and manufactured 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 it with ease. Provides clear, powerful, best true sound. Devoted Service: Genuine G-MARK Microphone comes with 12-month manufacturer aurance and supportive customer service. Welcome to come to us for troubleshooting or replacement of discontinuous/defective parts. SPECIFICATIONS System parameters:Audio frequency response: 50Hz-18KHzDynamic range: ge 80dBSystem distortion: le1%Signal to noise ratio: ge 60dBIdeal distance: 80mOperating temperature range: 5 -4.5 Carrier frequency range:520-580 MHz TRANSMITTER Frequency stability: plusmn 0.005%Carrier output power: le 30MwSpurious radiation suppreion:>40dBModulation: FMMaximum modulation: plusmn 75KHzPickup mode: Dynamic microphoneUse power: 1.5V Battery powerconsumption: <30mAVolume: 37X 250mm (hand-held microphone) RECEIVER Receiver sensitivity: <2muV Mirrorsuppreion:> 40dBTo increase: 50muSAudio output impedance: 600OmegaAudio output level: 0-0.5VUse power: AC110-240V 50 / 60HzPower consumption: 3WVolume: 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