3M 7000028549 Back-up Pad is designed for grinding applications with disc sanders and right angle grinders. It features a hook and loop attachment type, medium density rating, and a maximum speed of 6000 mps. The overall thickness is 0.31 in (7.87 mm) and it has a 5/8"-11 thread size. The pad is black in color and has a center hole diameter of 0.375 in (9.525 mm), with a regular type. It is suitable for use in the marine and metalworking industries, and in sub-industries such as builders hardware, medical instruments, metal fabrication, metal implants, plating & polishing, plumbing fixtures, and turbine engines.