Product details: Using TPA3116 The main circuit of n electrolytic capacitor signal adopts SMD electrolytic capacitor with a capacity of 4 x 470UF ensures strong and continuous power support. The selection of high-precision chip resistors ensures a good signal-to-noise ratio of the entire machine. The PCB is made of 1.6mm thick double-sided sheet metal, with a thickness of 2.0A copper, and a full process of tin spraying to ensure good current flow performance. First class PCB quality. adopts a fully enclosed dustproof potentiometer, which has more stable performance and is more durable than ordinary potentiometers!adopts a fully shielded high current inductor to ensure clear and powerful sound. Basic parameters: 1. Working method: Class D 2. Static current: 50mA 3. Work efficiency: 90% 4. Rated output power: 100W 5. Frequency response: 20Hz to 20KHz 6. Working voltage: DC18V to DC24V 7. Maximum output current: 4A Material: Aluminum alloy colour: Black Package Contents: 1 x Subwoofer Amplifier 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.