Check the listing for details. PAC APSUB-FD21 SubPro Interface for select Ford. Condition: New. Listed at 159.00 USD. Product highlightsconnect an aftermarket amp and subwoofer to your Ford vehicle's premium sound system factory amp needs to be left connected package includes amp installation module, Ford-specific harness, and wired remote amplifier module supplies 5-volt preamp signal for subwoofer amp options include flat frequency response or user-selectable center boost/cut frequency Ford-specific harness simplifies installation wired remote control included warranty: 1 year What's in the box34" T-Harness (24- & 54-pin plugs) w/inline 3A mini-ATO fuse AmpPRO module Remote level-control (attached 6' cable w/ 2-pin Molex plug) Instruction manual About this itemWritten by Crutchfield's Bob BihlmayerPAC APSUB-FD21 Modern cars often make it tough to add a subwoofer to your audio system. PAC's APSUB-FD21 interface allows you to add an amp and sub to the factory premium system in your Ford vehicle. The package includes an amp installation module, a Ford-specific harness, and a wired remote. The vehicle-specific wiring harness connects the amp module to the factory databus and supplies an unequalized 5-volt preamp signal for your sub amp. The factory amp needs to be left connected. The interface also allows you to select a center frequency to boost or cut to tailor bass response to your personal preference. This package also includes a wired remote control for adjusting your sub's level. You'll be able to upgrade your bass response with a minimum of fuss while retaining the functions, controls, and familiarity of your Ford radio. If you're looking for a simple way to add some bass to your Ford vehicle, the APSUB-FD21 gives everything you need to get the job done. This interface is designed for select 2011-20 Ford cars and trucks with premium sound systems.