During pipe layout, at junction points, it facilitates the connection/junction of a central branch to grooved pipe materials at both ends, which have varying nominal diameters.
| NO. | Size | External Dia.(mm) |
| 1 | 6''×125 | 159.0×133.0 |
| 2 | 8''×5'' | 219.0×133.0 |
| 3 | 8''×6''150 | 219.0×159.0 |
| 4 | 10''×5'' | 273.0×133.0 |
| 5 | 10''×6'' | 273.0×159.0 |
| 6 | 10''×8'' | 273.0×219.0 |
| 7 | 12''×5'' | 325.0×133.0 |
| 8 | 12''×6'' | 325.0×159.0 |
| 9 | 12''×8'' | 325.0×219.0 |
| 10 | 12''×250 | 325.0×273.0 |