2-Way Knob Volume Adjustment Switch Xy-Ka50l 50w*2 50w+50w Stereo Ble 5.0 Digital Power Amplifier Board Notice:- If It Is Used In A Car (12v Voltage), Please Use A Car Cigarette Lighter To Provide A Lighter Power Supply. Connecting To A Car Battery Will Generate Noise. -If It Is Used On A Truck (24v Voltage), It Needs A Step-Down Device To Reduce The Voltage To 12v Before It Can Be Used. Otherwise It Will Burn Out The Power Amplifier. -For Home Use, Please Use The 12v 2a Power Adapter. Mini Hifi Digital Bluetooth Audio Power Amplifier. Suitable For U Disk, Aux Input, Mp3 Format Playback And Bluetooth Wireless Connection. -Two Main Channel Output, Left And Right Channel Output Is Speaker Interface. This Machine Supports Bluetooth Operation And Line Input. Specification: Color: Blue. Channel: 2.0 Channel, Bluetooth: Support. Input Voltage: Dc 8-24v. Root Mean Square Power: 50w+50w, Maximum Output Power: 200w+200w Transmission Distance: 15m (Open) Input Mode: Bluetooth+Aux+U Disk+Usb Sound Card. Protection Mechanism: Power Supply Reverse Connection Protection, Short Circuit Protection, Self-Recovery Overheating Protection. . Size: 7.7 * 6.2 * 2.2 Cm/3.0 X 2.4 X 0.9 Inches/Weight 120g