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Welcome to our new Site We are adding some final touches. For other T-harnesses Options please visit Thank you
Welcome to our new Site We are adding some final touches. For other T-harnesses Options please visit Thank you

S.I.K GX:500

The first of its kind, our System Integration Kits don't just look great, they are made with the best tech

Miles above the rest

Quality is Everything

Double insulated with copper shielding and gold plated brass RCA ends

The Lair

All of our products are Designed, Tested and Manufactured by us
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Bass ROLL-OFF Who?

Gone are the days of cutting and splicing wires. Our R2G T-harness lets you add subs the right way in minutes

ONLY the best

We don't stock 20 brands that sell the same rebranded parts. We sell only the best of the best!
Free Shipping

When you spend $150+

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+1 (602)-320-7004

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We offer live chat support


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Automotive AMP RACKS

Collection list

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S.I.K Breakdown


You won't find our products on any website like ALIBABA. Everything we have is designed from the the ground up and for a specific purpose. When parts are not available we make them or find and retrofit them. Always with perfection in mind.

Always First

While other companies like to play it safe, we like to have solutions our customers need. No matter the challenge we will always have the solution first.

Perfection is our DNA

True Plug & Play

Our products are designed with our customers in mind. We have all experienced the price gouging, piss poor installation and care that can be associated to audio shops. At LLJ Customs we want to empower you with the Know-How, to do it your self better than any hack job audio shop ever will.

what our customers say

Thank you for a quality product! Before I researched putting in an amp and two 12' subs. I took my truck to a authorized Kicker dealer and told them what I wanted. The dealer absolutely hacked my system! It sounded like total shit. They told me it is what it is... Low and behold by the random chance I found a LLJ video about installing an amp andRead more about review stating Perfect

sub with the T harness...I've worked in the elevator trade for 30 yrs and I have extensive knowledge of control wiring. I was absolutely shocked they did such a horrible installation.
Thank you for your product after a year of trying to correct the problem and it took very little time!!

Lee F.

Hooked it up when I got it just to make sure it works. Ran it for a month on a sundown 1000w.amp, rms 1400 with a 15-in woofer and it beat the block up. Setting car alarms off, exactly what I wanted. Good looking out Llj customs.

Tisha G.

The Bose amp t harness was the perfect product to get a remote wire and rcas in my 2016 Chevrolet 2500hd. No wires running to the front of the cab clean installation. Plug and play is the perfect statement when referring to this product. Great job on the design and build. A+ in my book

Logan R.

ANC bypass dos the job, without all the bs.

Bobby L.

Installed in my 2018 Tahoe Premier RST after adding 2 12in kickers I had the most annoying hum in the speakers, this fixed it! Now it sounds wonderful! If you're Adding subs to your GM vehicle that has the Bose system with ANC I highly recommend this harness Best 20 bucks I ever spent!

David C.

Product worked just as it should.

Scott R.