5305-01-266-8564 (MIL-DTL-1222)
NSN 5305-01-266-8564 (NIIN 01-266-8564) 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 MIL-DTL-1222 (Military Specifications, CAGE 81349); also referenced as MIL-S-1222 (Military Specifications).
Key specs: 39 to 45 rockwell c overall hardness; full characteristics table below. NIIN assigned October 1987; DEMIL A (none required); unit of issue EA (each), $0.04 gov standard price.