| 1. Mounting Plate and Kingpin – A flat plate with an Integral Kingpin. |
| 2. Load Bearing (Commercial) – Row of steel balls or rollers that allow the yoke base to swivel. |
| 3. Yoke Assembly – The yoke base with legs welded on, and machined for the Main Load Bearings. |
| 4. Axle Bolt – The bolt on which the wheel revolves. |
| 5. Axle Bolt Nut – Secures the axle bolt to the yoke assembly to form the axle. |
| 6. Thrust Bearing – The row of bearings that operate between the yoke base and the retaining washer. |
| 7. Retaining Washer – Keeps the bearings retained. |
| 8. Kingpin Nut – Holds the swivel section together. |
| 9. Spanner Bushing – A tube that spans between the legs, over the axle, on which the roller bearing rides. |