Insert ball bearing unit is divided into heart and bearing seat, bearing on the term is added heart bearing housings, such as belt tight set screw outer spherical bearing UC205 with vertical UCP205 said. Insert bearing with housing is divided into heart and bearing seat, bearing on the term is added heart bearing housings, such as belt tight set screw outer spherical bearing UC205 with vertical UCP205 said. because of the strong interchangeability, the heart of insert bearing with housing can be fitting in the bearing of the same specifications different shape.