The scope of this standard is to define the following dimensional requirements for double hexagon, hexagon head and tee headed bolts, and nuts having a minimum tensile strength ranging up to 220 ksi, unless otherwise specified. a. Head dimensions (see 3.1); b. shank dimensions (see 3.2); c. geometric control (see 3.3); d. surface texture (see 3.4); and e. dimensions for nuts (see Section 4). For design calculations the SAE AS 8879 coarse threads, UNJC, shall be used for 0.164 thread sizes, and for smaller thread sizes use fine threads, UNJF. For particulars of thread runout and lead threads for bolts, see SAE AS 3062. NOTE. The ability of a design to achieve a given strength class will ultimately depend on the selected material and the associated processing To establish design requirements for bolts, screws and nuts in the UNJ thread inch series primarily for use on propulsion systems. As defined by the Federal Cataloging System, thread sizes less than 0.190 are referred to as screws and larger sizes are referred to as bolts. For the purpose of this document, the term bolt will be used for all sizes.