PSA Discs also known as Pressure Sensitive Adhesive discs are for use on random orbital and rotary sanders. PSA Discs from TAP come in disc rolls. PSA Discs are a coated abrasive with a paper adhesive backing. PSA Discs can come in a variety of abrasive grains such as, aluminum oxide, zirconia, silicon carbide, and ceramic. PSA discs are great for stripping, preparing primed and painted surfaces for finishing, sanding of plastics, fiberglass and composites, bare wood sanding, light weld blending, preparing and finishing metal, and sanding of all gel coat and body filler compounds.