Product name: 502T lead-type microphone and audio machine Product model: -502THS Chip model: TPA3116D2 Bluetooth transmission distance: 15 meters Input : Bluetooth + AUX + USB input + MIC Number of channels: 2.0 channels (50W + 50W) Adaptive power supply: DC12-24V/8A or above (cannot be connected to AC power) Adaptive speakers: left and right channels 20-50W | 4-822 External lead: 4 wires 30cm Protection mechanism: overvoltage, undervoltage, overheating, DC detection, short circuit protection Special functions: dual-channel microphone input Colour:Photo Color Material:Plastic+Metal Package Contents: 1 x Bluetooth amplifier board 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.