Screen Door Replacement Rollers These are replacement screen door rollers. We recommend replacing them if your screen door is becoming difficult to open and close. The old Sankyo Aluminum model number for this roller is 3K876. Please use this as a replacement for this roller. Since they are for both left and right sides, you will need two rollers per screen door. Product Specifications 3K screen doors, Noista screen doors, external sash screen doors, etc. For both left and right sides. Please secure with screws. Note: This price is for two rollers. *Product prices have risen and availability is very unstable. We recommend that you consider purchasing them as soon as possible.