This is the best grommet I have ever worked with. Seals up and locks down so the wire can not be pulled either way. Cost reflects the build quailty and performance. I have used this not only in automotive applications but also in marine applications which says alot for the performance.
4 AWG / 4 Gauge Firewall Bushing
- 4 Gauge Firewall Bushing
- Water tight seal when power wires pass through metal
- Locks securely as bushing is tightened
- Authorized Internet Dealer
- 1-year Manufacturer's warranty
Firewall Bushing Features
Warranty and Return Policy
Summary of Customer Ratings & Reviews
Kansas City, MO
September 15, 2011
56 of 66 found this helpful
October 21, 2011
This is great for going thru the firewall. Keeps the wire safe and secure from grounding out.
55 of 66 found this helpful
Olive Branch, MS
September 8, 2009
This will allow you to go through the firewall without having to worry about grommets or the metal cutting the wire. Great Idea for a product!
56 of 69 found this helpful
November 4, 2011
Worked like a charm could be alittle stronger plastic but still a good product.
50 of 60 found this helpful
July 22, 2012
I didn't use it. I bought my car used and the guy before me ran a system. I found the hole he used and it already had a rubber gasket type thing.
This could be very nice to have in some installation scenarios, like a complete rebuild.
Just know that you don't want your power wire chaffing on the firewall.
49 of 60 found this helpful
July 28, 2013
This feed through firewall bushing is a great product. I used it when I ran my power amp wiring through the firewall. Great protection, excellent size and very convenient. I definitely feel more comfortable knowing the wires are protected. I definitely recommend this to anyone routing a cable through a metal firewall.
46 of 57 found this helpful
Saint Louis, MO
April 2, 2017
Nice design to guide and waterproof the wire through the firewall. Tighten snug, not necessary to over tighten to waterproof. May need a helper.
0 of 0 found this helpful
When you look at the photo, there is a rounded cap end on the right, and a cap hex on the left.
Drill the appropriate size hole for the pass through bushing you are using. I would measure the hex threaded end on the left. Unthread the plastic hex and remove seal. Drill a hole in your firewall only the size of the threaded portion of the firewall bushing.
Once the hole is drilled - Paint or prime the steel to prevent rust/corrosion.
insert the seal back onto the firewall bushing, and then place in hole of firewall. The plastic thin threaded "Nut" will thread on the back side of the firewall holding it in place (In the inside of the vehicle). Try not to over-tighten - it is plastic.
The curved portion (right side of the bushing) will have a large cap that un-threads. This is a compression style connection. Un-thread the curved cap and slide your wire in and feed wire through the firewall bushing, then tighten rounded cap down. Inside, there is a rubber gasket that will compress down onto the wire as you tighten. Your wire should stay in place and not slide in and out.
The goal of the firewall bushing is to make sure you have a secure and water tight seal.
The FB4 was a bit sloppy with 4GA wire, but appears to seal fine on my application.
This will not work if you have a bundle of separate wires.
Internal Product ID
Wiring Diagram Legend
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