Found this holding the exhaust pipe on the manifold on a 6 cylinder 66 c10 I’m helping a buddy with. One side of the exhaust manifold was almost rotted away and someone years ago clamped the pipe to it with this. I ran it through my blast cabinet to get rid of the rust and crud hoping to see a name. The only markings are model 105, forged, SD5T and there a crown symbol on the end with the bolt.
