Originally posted by warmonger: You're funny by the way, showing me what an SAE bolt hardness rating is. Anyhow, you are right. I do not know for positive. On the other hand I looked at enough bolts during my years of experience and more recently during my hardware selection to realize how to identify what the higher metric grade bolts were commonly coated in. I learned that the various hardness bolts most of the time had different coloration that went along with the head style, and those look like grade 8.8 hardness bolts to me.
Here's another view... Spot-on visual assessment btw.
