The Power TM400X4ad 400 Watt 4-channel ultra-compact, amplifier is built on Rockford Fosgate’s proprietary Class-AD technology, featuring Constant Power to produce the same output at both 4-Ohm and 2-Ohm impedances. Flexible vehicle integration enabled through low-level and high-level inputs with auto turn-on. Top mounted controls allow easy access to built-in crossover and C.L.E.A.N. input/output clip detection circuits. The 3-stage thermal lock extrusion with dual fan forced induction keeps everything cool while real-time thermal/protection schemes safeguard the amplifier. Rockford Fosgate proprietary Class AD technology 4/2 Ohm muti-impedance Constant Power Differential inputs with high level auto turn-on feature 8 AWG power/ground connector w/ upgraded RCA connectors Remote-Out feature when using high level inputs 2/4 channel input switch 4 Ohm bridged capable C.L.E.A.N. input/output clip detection and indicator LEDs Top mounted controls Dual fan cooled Real time thermal sensing Dual extruded heat sinks Discrete surface mount technology Marine grade two part epoxy coating on circuit boards