FC 22-521C 22" .035"/180 Mid Grit Cylinder Scrub Brush for Factory Cat and Tomcat Floor Scrubbers. These have the old slotted hubs. For models with serial numbers BELOW 5000. Manufactrued with long lasting nylon impregnated with .035" diameter silicon carbide granules. These mid grit brushes can be used on most painted shop flooring, older sealed concrete, unsealed concrete, tile, stone, terrazzo, quarry tile, rubber, textrued synthetic flooring and other surfaces. The long trim scrub brushes can reach into grout lines for excellent cleaning results. Designed for everyday general duty cleaning of dirt and debris. Great for textrued flooring surfaces. Not for use on newly painted or high gloss flooring. Slightly more aggressive than Light Grit. Equivalent to Midi-Grit, Scrub-Grit II, Clean Grit. Commonly blue, grey, or rust in color. Replaces blue floor pads. Fits many popular models including, but not limited to, Mini 24, 22, 2200, and 2200EX, 2000C, 250C, GTX (24" Cylinder Models), Magnum (24" Cylinder Models), MiniMag (24" Cylinder Models), and others (These brushes overlap slightly to create a 24" scrub path). Please refer to your parts manual for the proper application. We offer a lighter grit (our FC 22-521PS) or heavier grit (our FC 22-521S). For newer "star" drive hub brush for models with serial numbers 50000 and above, search for 225-821C. Two brushes are required on most models. Priced Each. Replaces Factory Cat 22-521C. Our Part Number FC 22-521C