1. Use UHF676 to 697MHz frequency band (channel A: 677-686MHz; channel B: 687-696MHz), strong anti-interference. 2. Use 24Bit/48KHz high-performance audio dedicated A/D and D/A processing. 3. Use ID code + frequency for data encryption and frequency (even if the same frequency is used, when the receiving chip is interfered by RF, it will only affect the connection 4. The receiving distance, there will be no interference noise, if the two receivers are separated by a certain distance (such as 10 meters), frequency reuse can be considered. 5. It has an automatic mute and impact elimination circuit to avoid the impact and noise of the switch. The hand microphone has an LED digital tube display function, which can directly display the current frequency. The effective distance of wireless transmission is 30-50 meters. colour: black + blue Material: metal Size: 250x45mm Package Contents: 1 x receiver 1 x black microphone 1 x blue microphone 1 x data cable 2 x AA batteries 1 x 6.5 conversion head Only the above package content, other products are not included. Note: Light 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.