| Nominal Diameter, D | L 1 | L 2 | D 2 | □ |
| Form C | ||||
| NPT 1/16 X 27 | 65 | 19 | 7 | 5.5 |
| NPT 1/8 X 27 | 65 | 19 | 7 | 5.5 |
| NPT 1/4 X 18 | 70 | 25 | 11 | 9 |
| NPT 3/8 X 18 | 75 | 26 | 12 | 9 |
| NPT 1/2 X 14 | 80 | 31 | 16 | 12 |
| NPT 3/4 X 14 | 100 | 33 | 20 | 16 |
| NPT 1" X 11.5 | 110 | 38 | 25 | 20 |
| NPT 1.1/4 X 11.5 | 125 | 41 | 32 | 24 |
| NPT 1.1/2 X 11.5 | 140 | 42 | 36 | 29 |
| NPT 2" X 11.5 | 160 | 44 | 36 | 29 |
| NPT 3" X 8 | ||||
