Support Bluetooth, AUX, U disk, sound card audio mode U disk format supports MP3, WMA, lossless WAV/FLAC/APE The use of high-quality materials is guaranteed Good heat dissipation characteristics for greater power output Volume potentiometer with multi-function button Product name:300W x 2 dual-channel Bluetooth power amplifier board Power amplifier chip:TPA3255 Product model:ZK-3002B Adaptable power supply:Working voltage range 18-50VDC, limit 53V. It is recommended to use a DC power supply with a voltage of 36-48V and a current of more than 10A. The higher the voltage, the greater the output power. Compatible speakers:3-8 ohms, 50-300W, 50W@24V, 300W@48V Heat dissipation method:thickened heat sink + air cooling Maximum power:2x300W@50V 4ohm, 160W@50V 80ohm Protection mechanism:input undervoltage, overheating, overcurrent, short circuit protection. There is no input anti-reverse protection, the positive and negative poles cannot be reversed! Colour:Black Material:Plastic Package Contents: 1 * 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.