- 5/16‑24 UNF plain castellated hexagon nut for airframe use on 5/16‑inch drilled‑shank hardware
- Carbon steel, cadmium plated per QQ‑P‑416 Type II Class 3 for corrosion resistance
- Hex, castellated design used with a cotter pin for positive mechanical locking in critical joints
| Type | Nut |
| Style | Castellated Hexagon |
| Size | 5/16" |
| Material | Carbon Steel |
| Max Temp. | Not Rated |
| Thread Style | UNF, 5/16‑24, right‑hand |
| Head Style | Plain castellated hexagon |
| Height | 0.38" |
| Locking Element | Secured with Cotter Pin |
| Mil-Spec | AN310-5 |
