Green rechargeable battery: The microphone is equipped with rechargeable battery, which can be directly. It can work for 3-5 hours after charging for 2 hours. We advocate environmental protection and can protect the environment. Metal wireless receiver and hand-held microphone, and solid shell, thick grille, make the sound more realistic and more effective in preventing noise. The high-quality core effectively limits feedback and interference, picks up sound smoothly and transmits it easily. Provide clear, powerful and best real voice. Frequency Adjustable: 2-channel UHF wireless microphone system, optional frequency: 630-660MHz. Using PLL frequency synthesis technology, it provides worry-free sound transmission, minimum loss and maximum feedback rejection. Smooth and fast infrared synchronization. How To Adjust The Frequency Of K8 Wireless Microphone: 1. Open the battery cover of the microphone; 2. After pressing the button once, the frequency of the handheld microphone will change; 3. When the frequency on the receiver is consistent with the frequency of the handheld microphone, the frequency adjustment is completed. Transmitter indicators: Wireless program:equipped with transmitter 1/4 wavelength whip antenna, Built in spiral antenna for handheld microphone Output power:high power 30mW; Low power 3mW Stray suppression:-60dB System indicators: Frequency range:630-660MHz Modulation mode:broadband FM Adjustable range:50MHz Number of channels:32 Channel interval:1KHz Frequency stability:+0.005% Dynamic range:100dB Audio response:80Hz-18KHz(3dB) Comprehensive signal-to-noise ratio: 106dB Comprehensive distortion:less than equal 0.3% will not follow reception Deteriorate due to distance Operating temperature:-10-+40 Operation: 1. The receiver is equipped with a built-in charging module. When the host is tumed off,the transmitter microphone can still be when the power is connected. 2. When the microphone is ,the charging sign flashes. When the microphone is fully ,the charging sign will stop flashing. 3. The handset will automatically mute after being inserted into the charging hole for 3 seconds,and turn off the handset power automatically after 5 minutes. 4. It can also be when the power is turned off by hand. Colour:Black Material:plastic+metal Package Contents: 2 x Wireless microphone 1 x Receiver 1 x Accessory Set Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.