Window Regulator Roller & Rivet installs on the end of the window regulator arms and slide into the window channels. If these parts are missing or cracked, window operation can be difficult or impossible. Replacing these when you have your doors apart will make sure you have perfecly functioning windows. #11287 will work on any 1955-1957 classic Chevy model that uses a 5/16" rivet. Three required per window; 12 per car.