AUX audio input + Bluetooth 2-in-1 HIFI level with filter 50Wx2 Bluetooth digital amplifier board.note The heat sink with glue needs to be pasted onto the chip.This product is full of materials, high performance, high price, high quality amplifier for HIFI music.The TPA3116D2 is a Class D amplifier IC from TI that has very high index parameters. The modulation frequency can be up to 1.2MHZ, and the high output distortion is less than 0.1%.With AUX and Bluetooth two audio input methods, 2-in-1. The potentiometer adjusts the volume with a switch for easy control of the volume, making it perfect for DIY speakers. With a filter inductor, the sound is round and clear. It adopts copper DC connector and fence type terminal. It can withstand current, no heat, no damage to the wire, good wiring and short circuit.Colour: BlackMaterial: PCB+Plastic+MetalFree DC head lead, compatible with the input interface of this product, even if you don't have a DC head adapter or battery, it can be easily wired.5.0 Bluetooth version, the transmission efficiency is higher, the transmission distance is farther.Precautions for use: The switch on the board is the standby switch. After the switch is turned off, the machine is in a low- standby state. To completely turn off the or unplug the DC plug on the machine for a long time.How to choose Bluetooth or AUX audio input mode? on the amplifier, connect the speaker, turn the audio knob blue light to turn on, turn on the phone settings - Bluetooth - search for "BT-WUZHI", and then click the connection, there will be a beep when the connection is successful, this When it is in Bluetooth mode, you can play music. The time you on, it will automatically connect with the phone.If you want to use AUX audio input, then disconnect the Bluetooth connection, there will be a voice prompt, insert the audio cable to play music. In AUX (LINE IN) mode, Bluetooth is automatically switched to Bluetooth mode.Note: The casing in the picture is not includedPackage Contents:1 x Amplifier board1 x heat sink1 x DC cableOnly 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.