Grinding Wheel, Masonry, Type 27, Depressed Center, 4" X 1/4" X 5/8" Arbor C24S-BF. Silicon carbide and dual fiberglass reinforced. Used primarily on ceramic, masonry, plastic and other non-ferrous materials. Quality made to provide fast, safe and dependable service. Designed to be used on right angle grinders. Quantity discounts available. Wheel Size: 4" Thickness: 1/4" Arbor: 5/8" Spec: C24S-BF Max RPM: 13,700 Tool Type: Right Angle Grinder