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Rockford Fosgate RFK4

4-gauge amplifier power wiring kit

20 Reviews

Item # 575RFK4

In Stock

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825 Gardens Blvd

109 South Carlton

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Our take on the Rockford Fosgate RFK4

This wiring kit does not include speaker wire or patch cables. You will need to purchase those separately, in order to complete your amplifier installation.

Your amp needs big power wires in order to deliver top performance to your sound system. Rockford Fosgate's RFK4 amplifier power wiring kit supplies everything you'll need to send power to amplifiers with fuse ratings of up to 100 amperes. Rockford Fosgate makes the 4-gauge cable from 100% pure crystal-oxygen free copper wire so you can count on maximum signal transfer.

Product Highlights:

  • amplifier wiring kit
  • cables meet or exceed the American Wire Gauge specifications and requirements
  • 17 feet of 4-gauge power cable
  • 3 feet of 4-gauge ground cable
  • 20 feet of 18-gauge turn-on lead wire
  • AFS/MAXI fuse holder and 100-amp MAXI fuse
  • assortment of wire termination hardware and cable ties
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's in the Box:

  • One 17' Power cable (4-gauge) in a red translucent jacket (has an in-line fuse holder and a ring terminal on the battery end)
  • 3' Ground cable (4-gauge) in a translucent gray jacket (with a ring terminal on one end)
  • 20' Turn-on lead in a blue jacket
  • 100-amp Maxi-fuse
  • Power Ring
  • Ten 4" wire ties
  • Plastic grommet
  • 2 Plastic butt connectors
  • Female quick slide connector
  • Male quick slide connector
  • Small red rubber boot
  • Large black rubber boot

I have had knee replacement done so I cant give you a review but your customer service is great

rickie, Sherman, TX


Rockford Fosgate RFK4 Reviews

Average Customer Review(s):

(20 Reviews)

Rockford Fosgate RFK4

rickie from Sherman, TX on 1/7/2018

Crutchfield Customer Review (What's this?)

I have had knee replacement done so I cant give you a review but your customer service is great



Nice wire

Brian from California on 9/21/2017

Crutchfield Customer Review (What's this?)

Nice cable and connectors. The cable flexes plenty and has a fuse holder that allows the fuse to be seen easily in case of a blown fuse. This is my 3rd set of this same type of Rockford Fosgate power cable.

Pros: Quality and flexible


Rockford Fosgate RFK4

MATTHEW from Columbia, MD on 9/7/2017

Crutchfield Customer Review (What's this?)

quality cable nice fuse holder

Pros: great stuff

Cons: none

Great cables

Brandon from Lake Ozark, MO on 5/26/2017

Crutchfield Customer Review (What's this?)

Good quality cables. Nice and flexible. Had plenty of length for crew cab with amp mounted under driver seat. Would have still been plenty if amp was mounted under rear seat behind the driver.

Pros: Good quality

Cons: Didn't come with the 60 amp fuse I needed (only 100 amp fuse). So I had to order that separate

Rockford Fosgate RFK4

Jim from Ohio on 4/28/2017

Crutchfield Customer Review (What's this?)

Nice flexible wire made install easy. Zip ties in the kit was a little on weak side for size of wire so I chose to use something bigger so I know the wire is going to stay where I put it.

Pros: Complete kit to get power to amp.

Cons: Small zip ties

Love the build-in fuse holder, perfect length

MikeM from Virginia on 1/9/2016

Crutchfield Customer Review (What's this?)

This is my third subwoofer installation. I've been an audio hobbyist since the 60's and am a repeat customer at Crutchfield. - Rockford Fosgate RFK4 wiring kit Really appreciate the build-in fuse holder, fuse, and the cable disconnects at each end of fuse holder near the battery. The cables were installed in a Toyota Avalon which is longer than most cars. I still had about 2.5 feet of cable to play with in the trunk. To secure the ground cable to the car body metal I had to use the supplied large connector lug. I did have to expand the lug using two pairs of large pliers before inserting the wire end and then had to use a very large and heavy vise to clamp the lug to the wire. I did not need to use any of the small wire connectors that were supplied. Used with: - Pioneer TS-W311D4 12" dual voice coil subwoofer - Sound OrdnanceT Bass Bunker BB12-125S sealed enclosure, 1.27 cubic feet - Rockford Fosgate Power T600-2 - T-Spec 1.5 farad Capacitor

Pros: build-in fuse holder and fuse AWG cable length

Cons: none

Quality kit

Anonymous from Honolulu, HI on 6/30/2015

Crutchfield Customer Review (What's this?)

Great quality amp wiring kit, wires are thick and flexible with nice quality sheathing. An old 8ga Efx kit does not compare in terms of quality. Installed in a ford ranger extended cab with plenty of wire to spare.

Pros: Great quality

Cons: Doesn't come with a patch cable


rabuckg from Oklahoma on 6/6/2015

Crutchfield Customer Review (What's this?)

Simple, clean and easy product to install.

Pros: Nice gauge size that can handle about anything you throw at it. I only have an 800 watt amp, but if I ever upgrade to more power, it is ready for it!

Cons: None

Great kit

Jeff S from Alabama on 4/3/2015

Crutchfield Customer Review (What's this?)

This is a great kit and the wire is of great quality. We installed this in a Ford F250 crews cab truck and the 17' power cable was not long enough, but we had additional high quality wire from a previous install. Recommend you measure closely to make sure you will have enough wire. The only negative was that the fuze holder location was already fixed in place and did not allow us to place fuse where we wanted without wasting wire.

Pros: Quality wire, everything included in kit.

Cons: fuse location was already determined.

Just what you need.

Wrangler from Maryland on 1/17/2015

Crutchfield Customer Review (What's this?)

High quality product. Cable is 100% copper and there is plenty of it.

Pros: quality

Cons: none

high quality

stan from michigan on 8/28/2014

Crutchfield Customer Review (What's this?)

this is a high quality amp installation kit. just what you would expect from rockford fosgate.

Pros: high quality, all the wires are more than long enough


Rockford Fosgate RFK4

Dillon from San Antonio on 8/14/2014

Crutchfield Customer Review (What's this?)

Just what you need to add an amp



Rockford Fosgate RFK4

Ed from LA on 7/31/2014

Crutchfield Customer Review (What's this?)

This is a nice kit and the wire is exceptional. Everything needed for installation is in the kit. Comes with a 100 amp fuse so if you need a smaller size you will have to purchase one. And, if you need a larger size better check into a different option. Larger size fuses are not compatible with this fuse holder. The 17' power cable may come as a challenge if you have a crew cab truck. It worked in mine with no wire to spare. I would recommend making a closely accurate measurement from where you will mount the power amp and the route you will be taking before purchasing.

Pros: Nice kit. Exceptional quality. Has all the necessities without paying extra for unnecessary frills.

Cons: Make sure your amp doesn't need a larger than 100 amp fuse. Wire length may be a challenge if you don't do some pre-measurements. Especially on crew cab trucks.

Great Wiring Kit

BlameTheBird from Destin, Florida on 4/25/2014

Crutchfield Customer Review (What's this?)

This cable is very flexible, which made it easy to run through my truck. The plastic firewall grommet that comes with this takes a 5/8" hole and then the cable fits loosely through it. I went and got a 1/2" rubber grommet, and then dressed out the opening so that the cable would just slide though the hole. I attached the power cable straight to the tightening bolt on the battery terminal without having to modify the attached connector and was able to attach the 2' long negative cable to a seat mounting bolt once I filed the hole in the attached connector out a little. Overall, a nice setup, other than the fact that it came with a 100 amp fuse and my amp recommended an 80 amp fuse. A little pricy, but with the 50% off deal from Crutchfield when I bought this at the same time as I bought a power amp made it very worth the price.

Pros: 17' long positive cable was plenty long to wire my pickup truck. Supple cabling is easy to run.

Cons: Plastic grommet seems a bit lacking.

Worthy amplifier wire kit.

Amplifier wire kit. from Chesapeake, VA on 3/18/2014

Crutchfield Customer Review (What's this?)

Good value for your buck.

Pros: Won't dent your wallet

Cons: None


Mike K. from Plainfield, Illinois on 11/23/2013

Crutchfield Customer Review (What's this?)

Good quality wires with enough to get the job done right!

Pros: Fine quality wires and not cheapy stuff!

Cons: None

Rockford Fosgate RFK4

GeorgeD from Atlanta, GA on 4/9/2013

Crutchfield Customer Review (What's this?)

Good quality wires. some good hook ups plus a great fuse holder

Pros: N/a

Cons: N/a

Limited connection options

Jjkinsd from San Marcos, CA on 5/16/2012

Crutchfield Customer Review (What's this?)

Wire is great quality, provides power where you need it! Came with enough power and ground wire to wire a distribution block and two amps, so that's a plus!

Pros: Quality

Cons: Not enough crimp connectors for the #4 power and ground wire for one amp! In my opinion, at the price of this kit, you should be provided with more connection options as these can be hard to find around town. (I paid half price since I purchased with amp, thanks Crutchfield)

Perfect kit for sound board

Keith from Marrero, LA on 2/4/2012

Crutchfield Customer Review (What's this?)

Great package as wire and fuse was nothing like they used to put out with their amps. I ran it to a power distribution block to serve as the source power for all of my components. Everything was mounted to a piece of 1/2" MDF board so there was no need to run separate wiring for my subwoofer amp and sound processor.

Pros: Nice, complete package, 100 amp fuse was perfect as I had 2 other components running off of the souce power it provided. Easy to handle wire that also went through a spare grommet in the firewall.

Cons: It did not have a spare fuse; though you should not blow one anyway, it's still nice to have so you are not down should it blow for some reason.

Nice Kit.

Kevin from Mesa, AZ. on 6/19/2010

Crutchfield Customer Review (What's this?)

This is a nice kit and made it easy to wire in my new JL XD 600/6 amp. I was worried that the power and ground wires were a bit to short for my 2001 Chevy Silverado Z71 extended cab. However, there was plenty of wire for both the ground and power to wire in the amp under the back seat. The large gauge wire was plenty flexable to run around corners in the truck. The only downfall I can see it that I had to get a better firewall bushing to run the power wire to make sure it did not get nicked. I also replaced the included 100 amp fuse with a 60 amp fuse since JL recomended a 50 amp fuse if you run a single XD 600/6. Save your time running all over town getting wires and get this kit.




Hands-on research

Product Research


General Overview: This is a single amplifier wiring kit that includes the power and ground cables, turn-on lead, and other accessories required to install one amplifier. Speaker wire and RCA cables are sold separately.

High Strand Power/Ground Cable: The power and ground cable are 100% Pure Crystal-Oxygen Free Copper (PC-OFC) and meet or exceed AWG (American Wire Gauge) requirements.

In-line Fuse Holder: The included in-line, water-tight fuse holder attached to the power cable comes supplied with a 100-amp Maxi-style fuse (not pre-installed in fuse-holder). The fuse-holder will also accommodate an AFS-type fuse.

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

kit works best with factory radios. [ corey  Dec 11, 2017 ]
price and I got all fosgate products [ Jack  Nov 16, 2017 ]
The RFK4 has the power I need to rock my 2 Rockford fosgate subs without breaking the bank. [ Cj  Nov 08, 2017 ]
Makes wiring up my Fosgate amp a breeze. I can't source the components individually for this price. [ Mark  Oct 25, 2017 ]
Rockford Fosgate's reputation and product quality [ retalsb  Apr 24, 2017 ]
perfect for classic car sub woofer and pre amp installation. [ James  Mar 16, 2017 ]
Works great as an affordable, quality 5 channel amp. No complaints! [ M  Feb 08, 2017 ]
Rockford cables rock... [ ron  Nov 20, 2016 ]
was needed for installation [ Tim  Aug 25, 2016 ]
I needed this to hook up the MTX amp...not my first choice, but you can't get the one I want here [ Marc  Jul 04, 2016 ]
Clean and non tacky. [ Jovino Nevarez  May 11, 2016 ]
Only the best please [ DAVID  Apr 12, 2016 ]
so I could get the extra warranty and for a few more dollars than just a 100 amp fuse holder and fuse which I need to wire up my new rf 600x4 I got the power wire which I can use for future installs [ Christopher  Mar 30, 2016 ]
Clarence from support helped me Mach my subs to a amp very good service here I like dealing with crutchfield because they have fast shipping and excellent customer support [ Dustin  Dec 23, 2015 ]
Name, price, and what I was looking for [ DIEGO  Dec 21, 2015 ]
100% OFC and highest maxi fuse rating. [ Matthew  Dec 16, 2015 ]
I picked this amp kit for the extra year warranty that will come with purchasing the amp. [ William  Dec 13, 2015 ]

Looking for more? Check out the next model in this lineup.

Rockford Fosgate RFK4X

Get all the power and signal wires you need in one kit:

The Rockford Fosgate RFK4X offers these features:

  • one 20-foot twisted pair RCA patch cable
  • 30 feet of 16-gauge speaker wire