80 Grit “Grit-Backed” Floor Sanding Discs. Floor Polisher – Floor Maintainer – Floor Buffer Sandpaper. Premium 80 Grit – 17 Inch Floor Sanding Discs packed in a bulk box of 20 discs. This style of disc, “Grit-Backed, ” is made of durable paper and has “gripping grit” on the back side. The discs are used in conjunction with a thick floor pad and plastic or wood floor pad driver. The weight of the machine holds the sandpaper in place under the floor sander or floor polisher while sanding, and there is no need to use a special sandpaper driver with a center arbor. Used for general floor sanding using a 17″ floor pad driver and a 1″ thick pad as described above. Fits Most Floor Polishers that use a 17 Pad Driver and Pads: Clarke, Sanitaire, Hawk, Unico, Tornado, Alto, Dayton, Mercury, Saturn. Ernie’s Supply also offers a complete selection of other grits and products which you may need to complete your project. Ernie’s Supply offers quality floor sandpaper and flooring abrasives. Thank you for your business and as always, we wish you success with your projects. Please note the picture is a general photo of a “Grit-Backed” sandpaper disc and may not reflect the exact grit you will receive in this listing.