This SAE Part Standard covers selected screws, hex bolts, and nuts manufactured in accordance with American Society for Testing and Materials (ASTM) fastener standards. This document covers materials often used in ship systems and equipment but its use may be applied wherever fasteners of the covered materials are used. This document permits the fasteners covered to be identified and ordered by a part or identifying number (PIN) as defined in this document. The purpose of this document is to assist the designer and other personnel in providing requirements and part identifying numbers for the most commonly used fasteners for ship systems and equipment. A part identification number (PIN) is normally required for all military applications and provides a useful means of communicating fastener requirements to suppliers and manufacturers in a very succinct manner.