Construction typeArmDatum diameter18.7500 in, 476.25 mmMaterialCast ironNumber of grooves1.0000O.D. (in)18.7500 , 476.25 mm
| Construction type | Arm |
| Datum diameter | 18.7500 in, 476.25 mm |
| Material | Cast iron |
| Number of grooves | 1.0000 |
| O.D. (in) | 18.7500 , 476.25 mm |