The radiator as shown in the finished board strip diagram may not be enough in actual use at medium to high power. You can install a radiator according to your actual usage. Can be used with 300W pure copper wire toroidal transformer. High and low voltage power supply. Power supply voltage: AC dual 24-36V, transformer power recommended to be above 300W. Output power: 200Wx2 Impedance:4-8Ohm Note:Due to different production batches, the appearance is different, which does not affect the use. Colour:Green & Black Material:PCB+electronic components+Metal Package Contents: 1 * Power Amplifier Board 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.