Head TypeHexagonal (wrench-friendly)
ThreadingPartial (only the lower part of the shank is threaded)
StandardsDIN 931, ISO 4014, IS 1363
Common Grades4.6, 8.8, 10.9, 12.9 (metric); Grade 2, 5, 8 (imperial)
MaterialMild steel, alloy steel, stainless steel
Surface FinishZinc plated, black oxide, hot-dip galvanized, self-colored

