Rockford Fosgate RFK4 4 AWG Power Installation Kit

The Rockford Fosgate RFK4 is a 4 AWG power installation kit for adding an aftermarket car audio amplifier. It provides the primary power, ground, remote-turn-on, fuse protection, and termination hardware needed to establish an amplifier power connection. This power-only kit is intended for installers building a system with separately selected signal and speaker wiring.

Designed for vehicle audio upgrades that call for 4 AWG connections, the RFK4 helps create an organized electrical path between the battery and amplifier. The kit includes a long red power cable for the battery-to-amplifier run and a shorter ground cable for a nearby chassis ground point. A blue remote wire is also included to provide amplifier turn-on control from a compatible source unit or interface.

This kit does not alter the sound character of a system directly, since it is not an audio-processing component. Instead, its role is to support dependable power delivery for an appropriately matched amplifier installation. The power-only format makes it useful for systems where RCA cables, speaker wire, distribution blocks, or other accessories are chosen separately.

Rockford Fosgate specifies full-spec cable that meets or exceeds AWG requirements, using 100% pure crystal-oxygen-free copper conductors. The 4 AWG cable has a 21.1 mm² conductor area and 1,862 strands. These construction details support a true 4 AWG wiring foundation rather than relying on undersized cable labeling.

A MAXI fuse holder and 100-amp fuse are included to protect the main power run. Appropriate wire termination hardware is supplied for the installation. The RFK4 is a single-amplifier power kit, so it is a practical starting point for a compatible amplifier system that does not require a dual-amplifier distribution setup.

Key Features

• Full-Spec 4 AWG Cable: Meets or exceeds AWG gauge requirements for amplifier power wiring.
• PC-OFC Conductors: Uses 100% pure crystal-oxygen-free copper cable.
• 21.1 mm² Conductor Area: Provides the specified cross-section for 4 AWG cable.
• 100-Amp MAXI Protection: Includes a MAXI fuse holder and 100-amp fuse.
• Power And Ground Cables: Includes 17 feet of power wire and 3 feet of ground wire.
• Termination Hardware: Includes wire termination hardware for installation connections.

Design & Installation

The RFK4 uses red power cable, transparent-silver ground cable, and blue remote wire for easier circuit identification during installation. Its cable construction uses pure crystal-oxygen-free copper, while the supplied kit hardware is intended to complete the primary power connection. The power-only configuration omits RCA signal cable and speaker wire, allowing those items to be selected for the specific system.

Route the 17-foot power cable from the battery to the amplifier through a protected vehicle pass-through, and install the included fuse holder close to the battery on the positive cable. Use the 3-foot ground cable at a clean, secure vehicle chassis grounding point near the amplifier, and connect the remote lead to a compatible amplifier turn-on output. Confirm amplifier terminal acceptance, wire-length needs, fuse requirements, and safe vehicle routing before installation; professional installation is appropriate when vehicle electrical work is unfamiliar.