5310-01-445-9267 (218295-3)
NSN 5310-01-445-9267 (NIIN 01-445-9267) is a double hexagon self-locking nut in Federal Supply Class 5310, Nuts And Washers — a nut having 12 drive points and 24 sides. Manufacturer part number 218295-3 (Eaton Corp, CAGE 59875); also referenced as AS3066-11 (Allison Transmission Inc).
Key specs: 38 to 45 rockwell c hardness; full characteristics table below. NIIN assigned June 1997; DEMIL A (none required); ESD/EMI-sensitive.