Crafted for enhanced durability and performance, these backing pads by United Abrasives are designed specifically for use with resin fiber discs. The medium-type pads feature exclusive Spiraculture™ technology, which incorporates spiral ribs that create airflow channels, extending disc life by an impressive 30% to 50%. Each pad includes a nut, ensuring ease of use, and although additional nuts can be purchased separately, it is important to note that these pads are not compatible with SAIT-LOK™ quick change fiber discs. With a maximum RPM of 11,000, these 4-1/2" pads offer reliable support and strength, making them a valuable addition to any toolkit for high-performance applications.