The unbalanced-to-balanced board can be used to match the power amplifier board with differential input (balanced input), or it can be used as a dual-channel power amplifier board to change the output. The power supply adopts LM317+LM337 adjustable regulated power supply Working voltage: AC dual 5v-16v; DC dual 7v-24v The power supply defaults to a dual 12v working voltage, which is suitable for use with dual 12v . Colour:red Material:PC+metal Package Contents: 1 * DRV134 unbalanced to balance board 1 * Link line Only the above package content, other products are not included. Note: Light 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.