Holdding Small Digital Audio Motorcycle Stereo Amplifier 15W+15W Dual-channel Power Amp 6V-18V TDA7297F with No Static Noise Chip: TDA7297 Dual-Channel Amplifier Chip Power Supply: DC 9-18V, Recommend 12V 2A Output Impedance: 4-8 ohms Efficiency: up to 90% Dimensions: 48*50*43mm