ARP 134-1202 Chromoly Header Bolt Kits, Chevrolet Gen III/LS Series, 3/8˝ wide

I used these to replace the OEM bolts for my factory manifolds during an engine swap in my 2008 Chevy 2500HD, 6.0 liter gas LS engine. The factory bolts break often, especially the rear bolts. I used these hoping they won’t break. So far so good. But it’s only been a few thousand miles. But they do fit perfectly in factory manifolds.