Pearl® Redline™, Max-A.O.™ DCRED50H Grinding Wheel, Type 27 Depressed Center, Outside Diameter: 5 Inch, Thickness: 1/4 Inch, Arbor Hole / Thread Size: 5/8-11 Thread, Grade: R, Grit: 24, Abrasive Type: Aluminum Oxide, Max Speed: 12000 Rpm, Mounting: Threaded, Product / Materials Abraded: Ferrous Metals/Iron/Steel/Stainless Steel