Mr. Gasket 7421G Solid Aluminum Collector Header and Muffler Gasket, Silver

Flanges that are warped cannot be fixed with this method. To get these to work, your mounting flange must still be within a certain degree of straightness; otherwise, you'll still have a leak. Because the collector was slightly warped around the flange and wouldn't sit straight without replacing the entire collector, I decided to use a metal donut gasket inside the header for one side. I still give it 5/5 stars because this wasn't the gasket's fault. Additionally, the bolts appear to be of good quality.

Musa Clay

| Jan 26, 2021

Gasket continues to spout nonsense. I'm not going to buy anything else for Mr. Gasket after this. This kit has been in my possession for approximately four months. Locking nuts, thread lock, or at the very least lock washers should have been included. If you don't go under your car every few months to tighten everything up, the nuts will fall off.

Camila Silva

| Oct 25, 2021

I've used these on collectors and exhaust flanges for years and have never had a leak. After many years of use, I had never had a problem with loose bolts.

Dominik Stephenson

| Jul 31, 2021

I have no issues with anything I purchase.

Deacon Goodwin

| Dec 20, 2021