These gold sanding discs are made from aluminium oxide with a special treatment of calcium stearate which is resin bonded to provide self-sharpening and anti-clogging performance. The heavy-duty D-Weight backing paper makes the sanding disc more durable - able to withstand the toughest jobs. The hook and loop backing offers decent adhesion to facilitate the fast changing of sanding discs. The 15 pre-punched 8mm holes improve the dust extraction during sanding. Ideal for sanding and finishing wood, metals - including ferrous alloys, painted surfaces, varnish, plastic and fillers. Compatible with all 150mm random orbit sanders with a hook and loop backing pad, including Draper Stock No. 58097 and 89522.