FC 325-821C 32" 18 Single Row .035"/180 Mid Grit Abrasive Cylinder Scrub Brush for Factory Cat / Tomcat Magnum 34, GTX 34 Scrubbers with the New Style Splined Drive Hubs. A middle grit scrub brush for general duty scrubbing tasks. Narrow .035" diamater Tynex-A or Hahls Nylon filament impregnated with 180 grit silicon carbide granules for reaching small cracks and into grout lines. Equivalent to Midi-Grit. (Listed as a 34C New Style - 34" scrub path with brush overlap). These have newer splined hub with 6 notched hubs. For models with serial numbers ABOVE 50000. For older models with serial numbers BELOW 50000 with the slotted type drive hubs, use 32-521C. May fit models that have been converted to new splined brush drives which include 34, 3400C, 35, 35SS, 38, 40, 40HD, and 350 (32" Cyl. Models). Please check your model and brush drive type before ordering. Commonly blue in color. Equivalent to Midi-Grit, Scrub-Grit III, Blue Grit and Clean-Grit. 2 brushes required. Priced Each. Replaces Factory Cat / Tomcat 325-821C