Posted by Dave in CA [108.162.215.85] on Thursday, July 27, 2017 at 11:20:31 :
In Reply to: Dodge Bolts and nuts posted by Gary Troxel [108.162.245.199] on Wednesday, July 26, 2017 at 18:38:36 :
The marking on the head of the bolt indicates the supplier. An "A" is likely from Automatic Screw Machine Products Company, Chicago, Illinois. There were several other suppliers, too, each with their own, unique marking.