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Rockford Fosgate RFK4X

Complete 4-gauge amplifier wiring kit
Includes patch cable and speaker wire

26 Reviews | 1 question - 2 answers

Item # 575RFK4X

In Stock

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825 Gardens Blvd

109 South Carlton

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Our take on the Rockford Fosgate RFK4X

Your amp needs high quality wiring in order to deliver top performance to your sound system. Rockford Fosgate's RFK4X amplifier wiring kit supplies everything you'll need to send power and signal to your amplifier and speakers, including power cable, patch cable, and speaker wire.

This wiring kit includes patch cables and speaker wire for a 2-channel or mono amp — you'll need to add cables and speaker wire for multi-channel amps

Your amp needs high quality wiring in order to deliver top performance to your sound system. Rockford Fosgate's RFK4X amplifier wiring kit supplies everything you'll need to send power and signal to your amplifier and speakers, including power cable, patch cable, and speaker wire.

It's designed for amplifiers with fuse ratings of up to 100 amperes. Rockford Fosgate makes these cables 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
  • one 20-foot twisted pair RCA patch cable
  • 30 feet of 16-gauge speaker wire
  • MAXI fuse holder and 100-amp 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 MAXI fuse holder and a ring terminal on the battery end)
  • 100A MAXI fuse
  • 3' Ground cable (4-gauge) in a translucent gray jacket (with a ring terminal on one end)
  • 16' Twisted pair RCA patch cord
  • 30' of 16-AWG speaker wire
  • 20' Turn-on lead in a blue jacket
  • Ten 4" wire ties
  • 1 Plastic grommet
  • 5 Plastic butt connectors
  • 6 Female quick slide connectors
  • 5 Male quick slide connectors
  • Eight 16-AWG Spade connectors
  • 4 Blue rubber boots
  • 4 Black rubber boots

The wiring kit had everything I needed to connect my T1000X5ad. The wire and insulation were flexible and high quality.

Richard, Los Gatos, CA


Rockford Fosgate RFK4X Reviews

Average Customer Review(s):

(26 Reviews)

Rockford Fosgate RFK4X

Richard from Los Gatos, CA on 12/14/2017

Crutchfield Customer Review (What's this?)

The wiring kit had everything I needed to connect my T1000X5ad. The wire and insulation were flexible and high quality.



Good stuff

Justin from Kodiak, AK on 11/18/2017

Crutchfield Customer Review (What's this?)

Very nice product. High quality wire set that is very durable and very flexible which helps for installing in tight places! I gave it a 4 star rating due to the only thing i disliked was the way the fuse holder is designed requires the fuse to stick out and be exposed to the elements. i live in a very wet/rainy place where it rains 75% of the year. However , Other than that i love these kits!

Pros: Flexible, high strand count for more current flow. High quality all around.

Cons: Exposed main fuse in fuse holder to water/dirt.

Perfect gauges

Kapii from Dalhart , Texas on 8/18/2017

Crutchfield Customer Review (What's this?)

Outstanding equipment and perfect gauges

Pros: Exact size gauge for the power

Cons: N/A


Brycen from Long Beach, CA on 7/31/2017

Crutchfield Customer Review (What's this?)

easy to install.

Pros: Grate flex easy install.

Cons: none.

Great wiring kit.

Albert from Conway, AR on 4/9/2017

Crutchfield Customer Review (What's this?)

The Rockford Fosgate RFK4X wiring kit is definitely the kit to get. You can immediately tell that the power and grounding cables are good quality, high strand count which makes it flexible and easy to install. I used it to connect a Rockford Fosgate R1200-1D amplifier driving 2 Rockford Fosgate P2D2-12 subs. I installed this system in my 2008 Jeep Wrangler Sahara. I mounted the amp in the rear of the vehicle, the cable was perfect in length. I used all elements of this kit with the only exception being the speaker wire, since the subs are mounted in the rear I had plenty of wire left. I recommend retightening the power cable on both sides of the fuse holder. I also used dielectric grease on all my connections. Great kit, definitely delivering the power and a good signal to the amp.

Pros: High flexibility, easy to install.

Cons: None.

Watch your length

Brad from Champaign, IL on 3/15/2017

Crutchfield Customer Review (What's this?)

Overall good kit, the only issue I had is the lengths were not long enough for my Trailblazer. If you have a large vehicle with 3 rows of seating, this may not be long enough. I contacted Crutchfield and they took very good care of me.

Pros: Everything you need in 1 kit

Cons: Short lengths on large SUV's

Rockford Fosgate RFK4X

thomas from Oregon, IL on 1/16/2017

Crutchfield Customer Review (What's this?)

Decent quality wiring kit for the money



Rockford Fosgate RFK4X

Todd from Port Orchard, Wa on 1/16/2017

Crutchfield Customer Review (What's this?)

Better than your average kit. The inline fuse box on the power wire has a locking feature so you don't have to worry about it vibrating out



The hookup

Karl from Dundas, MN on 7/5/2016

Crutchfield Customer Review (What's this?)

This is yet another excellent product from Rockford Fosgate. The only issue I have with it is that it is supposed to be for a 4 channel amp but only comes with one RCA cable. Otherwise, everythign you need is here to install a 4 channel amplifier.

Pros: sturdy looks good

Cons: needs second set of RCA cables for 4 channel amplifier set up

amp Kit

mason from peoria IL on 5/9/2016

Crutchfield Customer Review (What's this?)

This kit was everything I needed to hook up my amp. It was nice not worrying about if I have all the part and wires i need, since everything you need are included.

Pros: Everything you need to get everything hooked up

Cons: none

Great product

Trent from Florida on 11/30/2015

Crutchfield Customer Review (What's this?)

Great product! Everything was really good quality and all wires were plenty long enough for my install . its nice because you don't have to worry about forgetting anything its all in one package .



Good Quality

Jukebox from Scott La on 6/19/2015

Crutchfield Customer Review (What's this?)

Solid lil wiring kit not too pricy and just what I needed.

Pros: High grade wire and the fuse block was of good construction.

Cons: I would like to see different grounding options included with these kits. Like the terminals that have three holes to get a better ground when you can't get to a bolt location.

decent enough

Spud from Volcano, HI on 3/23/2015

Crutchfield Customer Review (What's this?)

not bad. everything u need. good quality wire as well. little pricey, but works well. dont get voltage drop or amperage loss at end of 17' run.

Pros: good main wire, good speaker wire, good rca cables

Cons: maxi fuse.... not water tight casing...... make sure its in a good dry spot...... connectors not soldered only crimped. for the price, they could have upped the 'perfectionism' of it. fosgate claims top of the line.... so prove it



Crutchfield Customer Review (What's this?)




Wiring Harness

Terry from Corbin, KY on 7/10/2014

Crutchfield Customer Review (What's this?)

Super quality you get what you pay for.

Pros: Everything they claim

Cons: None

Wiring Harness

Anonymous from Vallejo California on 6/14/2014

Crutchfield Customer Review (What's this?)

Everything I needed was in the package. Crutchfield takes all the thinking out of the process with the research they put into the product line for you.



Just what I expected.

Dan C. from Cbus, Ohio on 5/13/2014

Crutchfield Customer Review (What's this?)

good set of high quality well insulated cables that when bought with my amp were 50% off just what I expected plus gets you a second year of warranty when used with your Fosgate amp so doubly sweet.

Pros: extra year of warranty and just what you need to install no extra bits needed

Cons: none that I can find other than extremely small terminal connecters on ground cable made it really had to find an actually bolt to fit it in my truck the connector was about a 10mm hole and the safety harness and bolt to my seats (only bolts near unit) are at least 14 mm so would like to see the preinstalled terminal connectors in a bigger size

Connects right to the battery without anything additional needed

Peczenij from Bethlehem, PA on 12/19/2013

Crutchfield Customer Review (What's this?)

Fine product. Speaker wire is only 16 gauge however - I would have preferred larger wire.

Pros: Connects to battery easily without needing anything else.

Cons: Fuse holder a bit confusing at first

RFK4X Amp Wiring Kit

Britt C from Richmond, VA on 9/22/2013

I have always trusted the Rockford Fosgate brand. You usually get higher quality products at a reasonable price. But I was disappointed when I opened the kit. The fuse holder was awkward to use, the RCA cables were low quality and the crimp connectors were junk! The only positive was the power cable and ground cable, they were top notch. All parts required for installation were there and my install went just fine but for the money I expected more.

Pros: Power and ground cables were high quality.

Cons: Crimp connectors, RCA cables and fuse holder were of lesser quality.

Amp Kit

Eddie from Knoxville, IA on 4/9/2013

Crutchfield Customer Review (What's this?)

Have everything you need to install the amp. What else can I say.

Pros: Everything as advertised.

Cons: none

Rockford Amp wireing kit

Cobster from Sargent, Ne on 2/13/2013

Everything is good but the RCA cables are cheaply made compaired to the rest of of the kit.

Pros: Cabels are 100% copper and super flexable

Cons: RCA cables are cheaply made

Great kit

DDC from Gallup, NM on 9/24/2012

Crutchfield Customer Review (What's this?)

All I needed to hook up my system. High quality wiring and works perfectly with the equipment I chose.



ticked off

Anonymous from Chicago Illinois on 6/14/2012

Crutchfield Customer Review (What's this?)

put everything in found out the patch cables or RCA cables we're defective

Pros: everything was great except for the patch cables

Cons: kind of expensive and my cables did not work should've tried another brand

Great kit, not so great price.

Garrett from OKC, OK on 3/18/2009

Pros: True AWG wire. High strand count <---That's a good thing. EXTREMELY flexible. You can pretty much tie this in a knot without worry of breaks, which makes it your best friend for complicated and cramped installs. The kit is complete with everything you need. More than you need actually! Cons: It's possible you will have to drill out or notch the power ring connector, but this is not difficult with a sharp drill bit or other "correct" tools. The connector is high quality however, so I guess that's a plus. Price. Even for such a great product, that's a steep one. REMEMBER: Be safe, don't mess with live wires!



Good kit

slvbeard from Central, MD on 9/5/2008

Good kit for the money, flexible thick wire. Works well.




GrandAm84 from Wisconsin on 1/13/2008

To start out i have 2 12" Rockfords with a amp. Before this kit everything was working fine but i hooked this up and nothing happend. i double checked everything and still dont know what i did wrong. Also the power cable end didnt fit the battery to good so i had to re drill that to. Overall pretty bad for what i was expecting from Rockford which has always been good to me




Hands-on research

Product Research


General Overview: This is a single amplifier wiring kit that includes the power and ground cable, turn-on lead, one pair of stereo RCA cables, 30' length of 16-AWG speaker wire and other accessories required to install one amplifier.

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 fuse holder attached to the power cable comes with a 100-amp MAXI-type fuse.

Patch Cord: Twisted pair cable design is used for noise rejection, a split center pin helps secure the connections at both ends.

Speaker Wire: The amplifier kits comes supplied with high strand 16-AWG speaker wire for increased sound transfer.

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?

The distance from my subwoofer Amp to battery required a 4 gauge wire. [ John  Dec 24, 2017 ]
Great price. High quality wires and fuse holder! Very easy to use for install! And great reviews from other customers [ Justin  Oct 24, 2017 ]
rocky recommended [ michael  Oct 10, 2017 ]
Suggested for amp [ Richard  May 18, 2017 ]
gotta have cable [ jaykub  Mar 12, 2017 ]
sub install [ DALE  Nov 25, 2016 ]
includes additional warranty period with Rockford Fosgate on my amplified [ Carroll Lewis  Nov 15, 2016 ]
4 Guage amp wiring it to get the power I need to where I need it [ Andrew  Nov 14, 2016 ]
Brand name and quality [ Jeremy  Oct 30, 2016 ]
I have used this in previous installs [ shaun  Sep 16, 2016 ]
Too of the line product [ Wanda  Jun 15, 2016 ]
Bought this to run subs in my 05 Cobalt SS [ Ethan  Jun 05, 2016 ]
Trusted brand [ Winston  May 28, 2016 ]
It was the cheapest option that offered a complete amp wiring kit with speaker wires. [ Joseph  May 17, 2016 ]
trusted brand, good reviews, discount pricing [ jay  May 08, 2016 ]
It added a warranty on the equipment. [ Lanell  May 06, 2016 ]
Great products from Rockford Fosgate, used them previously in my G35 coupe using the mutli-channel setup. [ jorey  Apr 16, 2016 ]
Complete package of what you need forthe wiring. [ Ricardo  Mar 28, 2016 ]
i need a wiring kit and trust Rockford above all else! [ CHRISTOPHER  Mar 07, 2016 ]
Good brand [ Douglas  Dec 23, 2015 ]
Good price for all needed items. [ Troy  Dec 16, 2015 ]

1 question already asked

All amp kits, as far as I am aware, only come with a single set of RCA wires. extra pair of RCAs is cheap and Crutchfield will take care of you:-) [ Barton  Feb 11, 2016 ]
By set it means 2 lines...which is 1 would run either the sub rca input...the left and right of front...or the left and right of rear...if it's a mono channel amp you don't need another cable set...if it's a multi channel amp you will need to by another cables set [ Homer  Feb 10, 2016 ]

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Includes patch cable and speaker wire