5305-01-145-9170 (3176209-C-059)
NSN 5305-01-145-9170 (NIIN 01-145-9170) is a socket head cap screw in Federal Supply Class 5305, Screws — an externally threaded fastener whose threaded portion is of one nominal diameter. Manufacturer part number 3176209-C-059 (Navair And Navsea Managed Original, CAGE 10001); also referenced as FF-S-86 (Federal Specifications Promulgated).
Key specs: 36 to 45 rockwell c overall hardness; full characteristics table below. NIIN assigned January 1983; DEMIL A (none required); unit of issue EA (each), $1.69 gov standard price.