Gives the dimensions and general requirements in a range of nominal sizes from ？ to 2 in. Detailed dimensions of bolts, screws, ordinary nuts, lock nuts, slotted nuts and plain washers are given and provision is also made for bolts faced under the head and machined on the shank, and machined nuts. Formulas for the calculation of dimensions for bolts and screw heads and nuts in intermediate sizes, and sizes larger than 2 in. are given in an appendix.
AS B148:1956 history
1970AS B148:1956 Unified black hexagon bolts, screws and nuts (UNC and UNF threads) and plain washers - Heavy series