Sound Storm Laboratories F4.400 400-Watt 4-Channel Power Amplifier with High/Low Crossover Max power 2 ohm 100W X 4 RMS power 4 ohm 50W X 4 Low pass crossover on CH3/4: 120Hz (fixed, 120Hz) Variable input gain control Low pass crossover on CH3/4: 120Hz (fixed, 120Hz) Variable input gain control Power and protection LED indicators Line and speaker level inputs Chrome plated RCA connectors and screw terminals