This 1958 Chevy Bel Air 2-Door Hardtop Quarter Window Regulator is an original GM part that has been professionally restored. We replace any gears or nylon rollers that are broken or worn down. Often the springs are broken or the main rivet is loose causing the regulator to fail to raise the window all the way up. In this case, we install new springs or rivets so as to ensure that the regulator will work properly. When we get done with them they look and function like new.