2 Pieces x 4" Hook and Loop backing pads and 2 Pieces 0.30" (8mm) round shank Drill Adapter for diamond polishing pads, sanding discs, buffing pads, and other grinding, sanding, polishing discs or pads with fuzzy loop backing. Backer pad is manufactured with durable phenolic plastic, premium molded urethane and nylon hook, which results in a flexible and highly resilient backing pad that minimizes heat transfer and conforms precisely to each curve and contour, with balanced and vibration-free operation, thereby producing exceptionally uniform sanding and polishing finishes. Max RPM 12,500. Pad features quick and easy sanding disc or polishing pad changes with the hook and loop attachment system. The pad’s closely arranged nylon hooks on the pad face prevent sanding or polishing pad from shifting, spinning or detaching. All Pro-Graad products are made with quality materials, which exceed industrial grade standards. We are driven to deliver high-quality, high-performing products to the end user. This is why we stand behind our 100% Product Guarantee. If you are not satisfied with the product, simply return your purchase within 30 days, and we will replace or refund your order. Pro-Graad is a USA Company with US Based Customer Support.