NVX True 400 watt RMS 4-Channel Bridgeable [Micro-V Series] Micro Class D Compact Car Amplifier [MVPA.4] Smallest amplifier perfect for tight-fitting spaces, size of deck of cards can support 400 watts True RMS Output Cutting edge Micro Class-D circuitry allows the amplifier to be extremely compact 3-way protection circuitry (thermal, overload, and speaker short protection) RMS power rating: 4 ohms: 50 watts x 4 chan | 2 ohms: 100 watts x 4 chan LED Indicators lights up green for protected operation or red to inform of a potential problem 4 ohms: 50 watts x 4 chan. 2 ohms: 100 watts x 4 chan. Variable low-pass filter (40-400 Hz) Variable high-pass filter (40-400 Hz) Input Sensitivity: 200mV-5V 8 gauge power and ground wiring is required for installation. Tested at 14.4 Volts 4-ohm Impedance load &lt;1% THD (Total Harmonic Distortion)