Planet Audio P8AWK 8 Inch Under Seat Powered Car Subwoofer, 800 Watts,

Built-in Amplifier - Amplifier Low Profile Subwoofers do not need external sources and are often very compact

Mosfet Power Supply - Improved switching speeds with MOSFET power supply, better performance with less power than drive, lower door drainage feedback capacity, lower thermal impedance for higher switching frequencies

Variable Low Pass Filter - The low pass filter is an electronic circuit that removes all notes below the filter's frequency setting. First you will use the Low Pass filter to keep the high notes away from your subwoofer

High and Low Level Inputs - Low (RCA) input is measured in voltage. High level (+/- cable) input is measured in watts. Both carry signals from your receiver to your amplifier to your speakers

Variable Bass Booster - Variable Bass Boost allows you to adjust low bass within the power range as you like