SMAKN&reg; Wireless Bluetooth 4.0 TPA3116 50W+50W Audio Receiver Amplifier Board Bluetooth 4.0 reception. Supply voltage: 8 - 26V DC. 3116 stereo power amplifier chip 2X50W, with a heat sink (recommended above 24V 3A power supply). Applicable Speaker Impedance: 4,6,8 ohm.