5305-00-057-1280 (FFS86TYPE1STYLE11)
NSN 5305-00-057-1280 (NIIN 00-057-1280) 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 FFS86TYPE1STYLE11 (Federal Specifications Promulgated, CAGE 81348).
Key specs: 36 to 43 rockwell c overall hardness; full characteristics table below. NIIN assigned January 1960; DEMIL A (none required).