Feature: 1. High performance, it uses a DC12‑24V single power supply, with TI's TPA3116D2 high‑performance digital power amplifier chip as the core, it can support 50W (left channel) + 50W (right channel) dual‑channel output. 2. Support Bluetooth audio receiver, it has external audio input interface, potentiometer with three tones of bass, midrange and treble, including function control switch and volume adjustment potentiometer. 3. Power‑saving design, it uses a wide working voltage, the efficiency is as high as 90%, you can use a good switching power supply, the switching power supply of a notebook computer, and you can also use a rechargeable bottle or a car power supply. 4. High‑quality board design, it is a finished board that has been welded and tested, with stable performance, sturdiness and durability, and a long service life. 5. Simple operation, you only need to connect the speakers as shown, connect the appropriate power supply, connect the Bluetooth audio device, or connect the correct audio input. Specification: Item Type: Power Amplifier Board Model: TPA3116 Material: PCB Purpose: Bluetooth Power Amplifier Board, Tuning Accessories Working Voltage: DC 12-24V (Current 3-4A, Such as The Above Power Requirements 20-24V / 5-6A) Bluetooth Receiving Distance: >Approx.8m / 26.2ft Bluetooth Version: 5.0 Sound Source Input Sensitivity: 600-800mV Frequency Range: 20Hz-20KHz Speaker Impedance: 4-8Ω Output Power: Power Supply 12V /8Ω Speaker:> 10W x 2 Power Supply 12V /4Ω Speaker:> 15W x 2 Power 21V /8Ω Speaker:> 30W x 2 Power 21V /4Ω Speaker: = 50W x 2 Power Supply 24V /8Ω Speaker:> 35W x 2 Power Supply 24V /4Ω Speaker:> 60W x 2. Package List: 1 x Power Amplifier Board4 x Twisted Key4 x Screw4 x Copper Head Nut4 x Nut4 x Gasket Note: 1. The actual test data and output power on the instrument are related to the power supply voltage/current, speaker impedance and the size of the audio input. When the power supply voltage/current is sufficient, the power supply voltage is usually higher, and the relative output power can be made larger. Speakers with different impedances also have different output power. Generally, speakers have smaller impedance and more power.2. If you want to use an alternating current (AC) transformer power supply, you must add a rectifier filter to the DC power supply, and the product can be used. Please note that the DC no‑load voltage should not exceed 25.5V (this is very important).