Rockford Fosgate RFK4D 4 AWG Dual Amplifier Installation Kit

The Rockford Fosgate RFK4D is a complete 4 AWG wiring kit designed to install and power a two-amplifier car audio system. It combines the main power, ground, signal, speaker, remote-turn-on, distribution, and termination components needed for a more organized installation. The kit is intended for installers and enthusiasts building a dual-amplifier system from a vehicle battery to two separate amplifiers.

A dual-amplifier installation needs more than a single power cable, since both amplifiers require properly routed power and ground connections. The RFK4D uses a 4 AWG main power and ground path, then includes 8 AWG branch cables and two distribution blocks for amplifier connections. This layout helps simplify power distribution when adding separate amplifiers for speakers and subwoofers.

The cable uses 100% Pure Crystal-Oxygen Free Copper conductors and is specified as full AWG cable. The 4 AWG cable uses 1,862 strands, while the included 8 AWG and 16 AWG cable also use high-strand-count construction. These materials support dependable power and signal routing in a vehicle audio installation.

For audio signal connections, the kit includes two twisted-pair RCA interconnect cables. Twisted-pair construction is used to help reduce noise pickup along the signal path between a compatible source unit and amplifiers. The included 16 AWG speaker wire provides cable for routing amplified output to speakers or a subwoofer enclosure.

The RFK4D is a practical foundation for a two-amplifier upgrade, with a fused main power cable, remote wire, speaker wire, distribution hardware, and installation accessories in one package. It is not an amplifier or speaker kit, so the amplifiers, source unit, speakers, and vehicle-specific integration parts are selected separately. Confirm each amplifier's wiring and fuse requirements before installation.

Key Features

• Dual-Amplifier Configuration: Includes wiring and distribution components for two amplifiers.
• 4 AWG Main Cable: Supplies main battery power and ground cable.
• PC-OFC Copper: Uses Pure Crystal-Oxygen Free Copper conductors.
• Twisted-Pair RCA Cables: Provides two signal cable pairs for amplifiers.
• 100-Amp MAXI Fuse: Includes fused protection on the main power run.
• Installation Hardware: Includes termination parts, grommet, and wire ties.

Design & Installation

The RFK4D combines full-spec AWG cable, PC-OFC copper conductors, distribution blocks, a MAXI fuse holder, and wire termination hardware. The main 4 AWG cable is supplied in red for power and gray for ground, while the branch cables step down to 8 AWG. Included cable types are sized for their designated roles: 4 AWG main power and ground, 8 AWG amplifier branches, and 16 AWG speaker wire.

Route the fused 4 AWG power cable from the battery, use the supplied grommet where the cable passes through a firewall, and keep power and RCA signal cables separated where practical. Use the two distribution blocks to feed the 8 AWG amplifier power and ground runs, then connect the remote lead, RCA cables, and speaker wire as required by the installed equipment. Disconnect the vehicle battery negative terminal before beginning work and follow the amplifier manufacturers' wiring, fuse, and grounding instructions.