Bottom plate covers the belts and brush roller of a Self-Propelled Hoover Windtunnel upright. Original part #42245030 (made in USA) updated to H-37245012 (china) both interchange. Last popular model this fits was the royal blue "Anniversary Editions". also fits first groups like U6425-900. All models use Style Y bags. Also fits the bagless twin chamber models. 3/10/22 dda