The Pioneer GM-E360X4 4-channel bridgeable amplifier is built for high power output and performance to deliver great sound. Features include large-capacity electrolytic capacitors for increased voltage stability and instantaneous output of large current. Improved circuit design using a PCB board made of glass epoxy substrate delivers high conductivity, increased temperature stability, and improved insulation resistance. For added flexibility, a variable LPF and HPF allow fine-tuning your audio system along with a two-step Bass Boost for optimal bass level adjustments according to listening preferences and music characteristics. This amplifier can be used with either OEM or Aftermarket HeadUnits.