The board features: 1. All components are as the new first-class products. The adjustment potentiometers are made of fully sealed type. The input and output terminals are made of pure copper terminals. The wiring is very convenient. 2. The op amp is from NE5532. The IC seat can be soldered at any time to change the op amp, and the effect brought by different op amps can be improved. 3, designed with LED indicators to monitor the power status in real time. 4. The PCB design of the board is simple and beautiful, and the wiring is reasonable, which makes the board have a very high signal-to-noise ratio and strong anti-interference ability. There is almost no noise near the horn when there is no signal input. size:78x32mm Material:PCB colour:green Package Contents: 1 * Subwoofer front panel 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.