Tapered roller bearings have tapered inner and outer ring raceways between which tapered rollers are arranged, optimizing rolling conditions. Tapered roller bearings are utilized in applications where there is a combination of radial and axial (thrust) loads. Tapered roller bearings are separable and have the following components: outer ring, inner ring, and roller assembly (containing the rollers and a cage). The non-separable inner ring and roller assembly is called the "cone", and the outer ring is called the "cup". Internal clearance is established during mounting by the axial position of the cone relative to the cup.

Therefore it is important to know the part number of both the cup and the cone, as they will most often differ and there are often many cup/ cone combinations available. While feasible to replace only the cup or the cone when replacing a tapered roller bearing, it is not recommended as it greatly decreases bearing life.