HBU2 – Generation 2 hub bearings
Generation 2 hub bearings have an outer ring with an integral flange, replacing the function of a separate hub. The flanged outer ring is designed as a lightweight structural component and incorporates threaded holes or studs to center and mount brake and wheel. They are typically used for non-driven front or rear wheels. Units for vehicles with wheel speed sensors include an impulse wheel (tone ring), typically located on the outer ring.