FC 18-421S 18" .050"/80 Nylo-Grit Abrasive Scrub Brush for Factory Cat Tomcat 350D, 52, 5100 Disc Brush Scrubbers which require 8 Point Brush Drive. Our second most aggressive stripping and heavy duty scrubbing brush. Long lasting .050" diameter DuPont Tynex-A Nylon is impregnated with large 80 grit silicon carbide granules. These brushes are designed for stripping jobs and heavy duty scrubbing jobs on most hard surfaces. Equivalent to Tough-Grit. Commonly black in color. Replaces brown or black floor pads. 17" diameter plastic block (18" scrub path) with an 8-point clutch plate (Please check your model for the proper number of points. We offer a 6 point and 8 point clutch plate. Use FC 2-421S for 6 pt.). We also offer a more aggressive brush for heavier dirt and debris (use FC 18-421SS, Super-Grit Equivalent). Fits Factory Cat and Tomcat 350D, 52 and Tomcat 5100 disc brush model floor scrubbers (Some of these models also take cylindrical brushes. Please check your model before ordering). Two brushes are required for model 350D, three brushes are required for models 52 and 5100. Priced Each. Replaces Factory Cat Tomcat 18-421S, 52-421S. Our Part Number FC 18-421S