5306-00-638-7253 (FFB575)
NSN 5306-00-638-7253 (NIIN 00-638-7253) is a machine bolt in Federal Supply Class 5306, Bolts — an externally threaded fastener designed for insertion through holes in assembled parts and normally intended to be tightened or released by torquing a nut. Manufacturer part number FFB575 (Federal Specifications Promulgated, CAGE 81348).
Key specs: unfinished head; 95 rockwell b maximum overall hardness; full characteristics table below. NIIN assigned January 1963; DEMIL A (none required); unit of issue EA (each), $0.68 gov standard price. Supersedes 5306-00-174-8344 (1979).