ITEM NAME:Bluetooth Stereo Digital Audio Amplifier Board with Receiver 3.5mm Output Product Description Description: Specification: Power amplifier chip: for Yamaha YDA138 Operating Voltage: 8.5-14 VDC (Power Input with Polarity Protection) Recommended power supply: 12V DC current 2A Output power: 2X10W (8 Ohm), 15W + 15W (4 Ohm) Output impedance: 4-10 ohms Product size: 60mm*38mm*8mm/2.36*1.49*0.31'' Packing weight: 15g Note: Please allow 1-3mm differs due to manual measurement. Due to the different display and different light, the picture may not show the actual color of the item. Thanks for your understanding. Included: 1 X Bluetooth Stereo Digital Audio Amplifier Board.Included: 1 X Bluetooth Stereo Digital Audio Amplifier Board. Power amplifier chip: for Yamaha YDA138. Output power: 2X10W (8 Ohm), 15W + 15W (4 Ohm). Output impedance: 4-10 ohms. Due to the different display and different light, the picture may not show the actual color of the item.