Concentric bushing, standard head, 303 stainless steel, delivered together with W guide wheels
| 4 | Size | |
| Standard | Head Profile | |
| Concentric (stationary) | Adjustability | |
| Metric | Unit version |
| HS | 22.4 mm | Head size |
| LO | 29.9 mm | Overall height |
| HH | 11.1 mm | Head thickness |
| THH | ±.001"(±0.03mm) | Tolerance head thickness |
| MV | 0.812 mm | Mounting surface to wheel vee |
| OD | 15 mm | Wheel mounting diameter |
| TOD | +0/-0.001"(+0/-0.025mm) | Tolerance wheel mounting diameter |
| LB | 18.8 mm | Wheel mounting length |
| ID | 10 mm | Mounting hole diameter |
| TID | +0.002/-0.001"(+0.051/-0.025mm) | Tolerance Mounting hole diameter |
| m | 42.4 g | Weight |
| M10 | Recommended mounting fasteners |
| BWC | PBC |
| MB4SS MB4 | VB4 |
