Composed of a washer with a raceway, a ball, and a retainer assembly. The raceway washer that matches with the shaft is called the shaft ring, and the raceway washer that matches with the housing is called the seat ring. This type of bearing includes unidirectional thrust ball bearings and bidirectional thrust ball bearings. Unidirectional thrust ball bearings can only withstand axial force in one direction and can limit axial displacement in one direction, while bidirectional thrust ball bearings can withstand axial force in two directions and can limit axial displacement in both directions. Neither can withstand radial loads. In addition to the structure with flat seat rings, there are also structures with spherical seat rings and seat cushions. The bearing has a high load capacity and a low limit speed.