180mm. Multipurpose kit for use on wood, metal and paintwork. Includes 1 x hook and loop backing pad, 1 x polishing sponge and 3 x sanding discs (40, 80 and 120 Grit). Also includes 1 x rubber backing pad, 1 x wool bonnet and 1 x synthetic bonnet. For use with angle grinders and sander polishers. M14 x 2 thread.