Industrial standards are: ISO, DIN, IDF, 3a, SMS, etc
SIZE | Φ | A | B | C | |
1" | 25.4 | 50.5(34) | 22.5 | 55 | |
1¼" | 31.8 | 50.5 | 28.8 | 60 | |
1½" | 38.1 | 50.5 | 35.1 | 70 | |
2" | 50.8 | 64 | 47.8 | 82 | |
2½ | 63.5 | 77.5 | 59.5 | 105 | |
3" | 76.2 | 91 | 72.2 | 110 | |
3½" | 88.9 | 106 | 84.9 | 125 | |
4" | 101.6 | 119 | 97.6 | 148 |