| Screw Thread | 5/16 | ||
| D | 0.3125 | ||
| P | 18 | ||
| B | Min | L≤10 | 0.875 |
| B | Min | 10＜L≤16 | 1.125 |
| B | Min | L＞16 | 1.625 |
| U | Max | UNC | 0.111 |
| U | Max | UNF | 0.083 |
| U | Max | BUN | None |
| Ds | Max | 0.3125 | |
| Ds | Min | UNC | 0.303 |
| Ds | Min | UNF | 0.304 |
| Ds | Min | BUN | None |
| Ds1 | Max | UNC | 0.303 |
| Ds1 | Max | UNF | 0.304 |
| Ds1 | Max | BUN | None |
| Ds1 | Min | UNC | 0.271 |
| Ds1 | Min | UNF | 0.281 |
| Ds1 | Min | BUN | None |