5305-01-059-0221 (BACB30AB-P8-31A)
NSN 5305-01-059-0221 (NIIN 01-059-0221) is a close tolerance screw in Federal Supply Class 5305, Screws — a screw, machine or screw, cap, socket head whose unthreaded portion is of specified grip length, plated or unplated. Manufacturer part number BACB30AB-P8-31A (The Boeing Company, CAGE 81205).
Key specs: 36 to 40 rockwell c overall hardness; full characteristics table below. NIIN assigned April 1978; DEMIL A (none required); unit of issue EA (each), $12.56 gov standard price.