Red Rubber for SUNMAX RT50, RT50+, RT50D, RT50D+, RT50DW, RT50AC, RT70,  RT70+  Floor Scrubber Machines. The Rubber for SUNMAX are wareable parts so they are not covered by warranty. We recommend replacing them every 1-3 months for standard applications, like cleaning smooth, indoor surfaces. For gritty, abrasive surfaces (like concrete or asphalt) or frequent use, replacement might be needed every 1-2 weeks. We also suggest adjusting the squeegee assembly’s angle and height. Ideally, about one-third of the squeegee blades should be in contact with the floor, tilted slightly forward at a 30-degree angle. After each cleaning session, please also clean the squeegee and suction hose.