This standard establis es the main dimensions and parameters of precis on screws with a hexagonal head from 1/4 to 3/4 in diameter, which are used as fastening elements.
NC 06-06-1985 history
1985NC 06-06-1985 Fixing Machine Elementa. Pre- cision Hexagonal-Head Screws from 1/4 to 3/4 in. Parameters and Main Dimensions
1967NC 06-06-1967 Precision screws with hexagonal head Diameter 1/4 to 3/4 inches