Grade 5 cap screws, fine thread, are dura-plated for corrosion resistance.  They are made in North America, rated for 120,000 PSI tensile minimum strength, conform to SAE J429 specifications and are DIC approved.  These cap screws have a rockwell hardness of c33-c39, exceeding ASTM, ANSI, GM, FORD, and CAT specifications.  They are also roll threaded to class 2-A thread fit, as well as head marked with the manufacturers symbol and  3 radial lines as shown below.  Certifications and destructive test results available upon request. 

 Grade 5