NSS 28-9-771-1 17" .050" Nylo-Grit Scrub Brush for NSS 1708 Series Walk Behind Floor Scrubbers. Heavy duty .050" Tynex-A or Hahls Nylon with 80 grit silicon carbide granules. The nylo-grit brushes are used for heavy duty scrubbing jobs on unsealed concrete, and for stripping of hard surfaces such as concrete and tile. These can be used for removing paints or sealers once stripper is applied. Heavy grit brushes should not be used on epoxy painted flooring, newer sealed concrete, stained concrete (Use Nylon - NSS 2897201). Usually black in color with a notable grit textrue. Replaces black floor pads. 17" diameter plastic block includes spin-on brush drive clutch plate (28-9-010-1). Fits NSS Wrangler 1708 series walk behind floor scrubbers. One 17" diameter brush required. Priced Each. These are bundled together to reduce freight when two are ordered. Replaces NSS 28-9-771-1, 2897711. Our Part Number NSS 2897711, 28-9-771-1