Thrust bearings are a type of rotary bearing that allow rotating parts to move smoothly while supporting axial loads (those parallel to the shaft) in one direction. They consist of roller elements encased in a cage, which sits between two thrust washers or raceways. Because they cannot support radial loads (where the load is perpendicular to the shaft), thrust bearings are a good choice for applications where shaft misalignment is unlikely. Thrust washers are flat washers that create a smooth surface for roller elements to ride on without wearing out. They help prevent movement along the axis of a shaft bearing an axial load. Thrust washers are typically used as fatigue liners for soft housing faces or combined with needle roller and cage assemblies for additional support.