PFERD 63403 Grinding Wheel, Type 27 Depressed Center, Reinforced, Pipeline, Performance Line SG-ELASTIC, Outside Diameter: 7 Inch, Thickness: 1/8 Inch, Arbor Hole / Thread Size: 5/8-11 Thread, Grade: R (Hard), Grit: 24, Abrasive Type: Aluminum Oxide, Max Speed: 8600 Rpm, Mounting: Threaded, Product / Materials Abraded: Steel