To fully define the following requirements for bolts with spline and hexagon heads of strength class up to but no including 1250 MPa: a. Head dimensions b. Shank dimensions c. Geometric control d. Surface texture This document is based on one class of thread after all processing@ including coating or plating@ has been completed as follows: tolerance class 4h6h. For particulars of thread@ see AS1370. For thread runout and lead threads@ see AS3062. To fully define the following requirements for nuts with spline@ plain hexagon and castellated configurations of strength class up to and including 1100 MPa: a. Nut dimensions b. Geometric control c. Surface texture For particulars of threads@ see AS1370. This document is based on the following classes of internal threads after all processing@ including coating or plating@ has been completed: Tolerance class 4H6H for sizes up to and including 5 mm Tolerance class 4H5H for size 6 mm and larger For particulars of thread@ see AS1370. Purpose: To establish design requirements for metric aerospace bolts@ screws and nuts primarily for use on propulsion systems. The smaller thread sizes are usually referred to as screws. For the purpose of this document@ the term bolt will be used for all sizes.