Metric Inch PRODUCT SIZEPROPERTY CLASSTENSILE STRENGTHSTANDARDHex Head Bolt / ScrewM4 to M8010.91040N / mm2 minISO 4017 (Full Thread)ISO 4014 (Half Thread) PRODUCT SIZEGRADETENSILE STRENGTHSTANDARDHex Cap Screw1/4 to 28150,000 psi minASME B18.2.1Hex Cap Screw1/4 to 25120,000 psi min (1/4 to 1)105,000 psi min (over 1 to 1-1/2)ASME B18.2.1Hex Bolt1/4 to 1A60 Ksi minASTM A307 / ASME B18.2.1