1The receiver has a charging function. Equipped with a detachable large capacity lithium battery. 2With automatic mute and impact elimination circuit to avoid the impact and noise of the switch on/off. 3The effective distance of wireless transmission is 2050 meters. 4Multiple devices can be used at the same time, without interference and frequency. 5With power and wireless indicator light.Features: 1. The receiver has a charging function. Equipped with a detachable large capacity lithium battery. 2. With automatic mute and impact elimination circuit to avoid the impact and noise of the switch on/off. 3. The effective distance of wireless transmission is 20-50 meters. 4. Multiple devices can be used at the same time, without interference and frequency. 5. With power and wireless indicator light. 6. Extremely high pickup sensitivity and excellent sound quality make your speech or singing easy. 7. Receive two-channel (stereo) output for a variety of audio amplification devices. 8. UHF frequency band is selected, the transmission distance is stable and the anti-interference ability is strong. 9. The receiver adopts automatic frequency lock design, which is easy to operate and intelligent. Specifications: Type: WirelessSize: Approx. 24*5.5*5.5cm/9.45*2.17*2.17inch Frequency range: 600mhz-700mhz Frequency response: 50hz-18khz Microphone battery: AA battery(Not included) Capacity: 950mah Receiver battery: lithium polymer battery18650(Not included) Capacity: 1200mah Working time: 10 to 12 hours Package List: 1 * Microphone1 * Receiver1 * USB Cable 1 * Adapter Head 1 * Microphone Cover 1 * Microphone Cotton 1 * User Manual Note: 1. The power supply voltage must not exceed the supply voltage range of this module. 2. Do not touch the components on the back of the module during work, so as not to affect the normal operation of the module or cause the short circuit to burn the module. 3. Check the user manual for detailed use. User settings: This module can be frequency modulated, generally it has been modulated. Under normal circumstances, do not use FM. If there is interference, you need to adjust the frequency. Under normal circumstances, do not arbitrarily mobilize, so as not to be confused by the channel. Frequency remodulated method: 1. Turned off the receiver and the microphone. 2. Unscrew the battery cover of the microphone, press the frequency button above the battery cover and press and hold the power button. Press and hold the two buttons for about 3 seconds while waiting for the display to flash. 3. Turn on the receiver and the receiver will flash for 3 times. 4. Press the microphone counter button and the receiver lights up to work normally.