Replacement Door Wheels for Sash Windows These are replacement door wheels for sash windows. We recommend replacing them if the sash window becomes difficult to open and close. The old TOSTEM model number for this door wheel is AZWS025. Please use this as a replacement. Since they are for both left and right sides, you will need two door wheels per sash window panel (four for a sliding window). ※ This price is for two door wheels.