FC 28-521SG 28" 18SR .018"/500 Soft Grit Cylinder Scrub Brush for Factory Cat / Tomcat 28, 2800C, 29, 3000C, 350C, 30 (MiniMag/Magnum/GTX30) Scrubbers. Not offered by Factory Cat or Tomcat. Our softest non-abrasive cylindrical scrubbing brush for light duty scrubbing jobs on polished, epoxy painted or other sensitive flooring surfaces. Long lasting, .018" DuPont Tynex-A Nylon filament impregnated with our lightest 500 grit silicon carbide granules. Lighter and softer than Light Grit. Fits Factory Cat and Tomcat 28, 2800C, 2800EX, 29, 3000C, MiniMag 30, Magnum 30, GTX 30 and 350C scrubbers which require two 28" cylindrical scrub brushes (Listed as a 30C Old Style - 30" scrub path with brush overlap). These are the OLD style scrub brushes with the slotted drive system (newer style is a "star" drive with six notches). These are for units with serial numbers BELOW 50000. Please check your unit before ordering. Two brushes required per unit. Priced each. 28-521SG