Fiber Disc, Abrasive Type Coated, Abrasive Material Ceramic, Backing Material Fiber, Backing Weight Not Applicable, Grit 50, Overall Diameter 5 in, Series Predator, Coating Coverage Closed, Resistance Properties Heat, Connector Size 5/8 In.-11, Connector Type Threaded Hole, Color Gray, Features Self-Lubricating Grinding Aid, Rigid Backing