Class D Amp Module For Diy Wireless Speaker With Mini Bluetooth Amplifier Board ?Output Power of ZK-502L?This little thing smaller than a card can output up to 50w*2 power (peak power). Wide voltage input: DC 5-24V, common power adapter can supply power for it. It is recommended to use a DC power supply between 12-20V. ?Bluetooth 5.0?User Can Directly Connect with Wireless Bluetooth 5.0 without Password ?Easy Installation and Short Start-up Sound?The Illustration Of Each Interface Is Printed On The Protective Plate, Making It Easy To Install Even Without Instructions. The Sound of The Amp Board To Start And Connect To Bluetooth Is Short . ?PROTECTIVE FUNCTION?Over Protective Function:This BT Amp Is Designed with Protective Case, Over-heat Protection, Short-circuit Protection ?BUY WITH EASE?We are committed to quality and customer service. 24/7, if you need any help. We will provide you with a 100% satisfactory solution.