5305-01-324-2587 (166378-4)
NSN 5305-01-324-2587 (NIIN 01-324-2587) 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 166378-4 (Navair And Navsea Managed Original, CAGE 10001); also referenced as NAS1351-06-16P (National Aerospace Standards).
Key specs: 39 to 45 rockwell c overall hardness; full characteristics table below. NIIN assigned August 1990; DEMIL A (none required); unit of issue EA (each), $20.65 gov standard price; ships at 0.01 lb / 0 cu ft.