This is a pic of an original 70-71 A-body Brake Prop Valve bolt head (It holds the proportioning valve to the inner fender).Nearly the same exact bolt style and length is also used for retaining brake line clamps to the undercarriage in various applications but the head stamping varies slightly as well as the head markings (likely same bolt, two vendors). Anyone know a source for these? Most are clear zinc plated but some I've seen were dark phosphate. Bolt is resting in a spare part for the 1st pic, ignore the background.