THIS IS FOR A 1956 1957 CHEVROLET 4 DOOR HARDTOP (NO POST) UPPER WINDOW STOP FOR THE REAR DOOR. THIS IS WHAT KEEPS THE REAR DOOR WINDOW FROM BEING ROLLED UP TOO FAR. IT CONTAINS THE PLATE, RUBBER BUMPER AND THE CORRECT LENGTH ADJUSTER THAT WERE ONLY USED ON A 4 DOOR HARDTOP. ONE KIT WILL DO ONE REAR DOOR WINDOW. 2 KITS REQUIRED PER CAR. SKU#2613