Features: Use original TPA3116. The electrolytic capacitor signal main circuit adopts a patch electrolytic capacitor with a capacity of 4×470UF, which ensures strong and continuous power support. High-precision chip resistors are selected for the resistance to ensure a good signal-to-noise ratio of the whole machine. PCB adopts 1.6mm thick double-sided board, 2.0 oz copper thickness, full tin spraying process, guaranteed sizeGood current passing performance. First-class PCB quality. Adopting fully enclosed dustproof potentiometer, the performance is more stable, and it is more durable than ordinary potentiometer!Fully shielded high-current inductors are used to ensure a clear and powerful sound. Connect the power supply (12-24V for DC power supply inside + outside -) and speakersPress the red power button to turn onUse your mobilephone to search for Bluetooth-compatible for pairingOpen the music player to for play musicDisconnect Bluetooth-compatible when using AUX inputNote: When using 3.5AUX, if the input audio signal is too large, the output will be distorted. compatible Specifications: Material:Metal Working method: Class D Quiescent current: 50mA Work efficiency: 90% Rated output power: 2x50W Frequency response: 20Hz to 20KHz Working voltage: DC18V to DC24V Maximum output current: 2A Size:Approx. 80x 80x40MM Package Includes: 1x TPA3116 TL074 2x50W Digital Tone Power Amplifier Board D-50B note: Please allow 1-2cm errors due to manual measurement,pls make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.