4″ x .035″ x 3/8″, Small Diameter Cutoff Wheel, Metal & Stainless Cutting & Grinding, Heavy Duty Aluminum Oxide Grain For Aggressive Cutting Action, Proprietary Material Mix Ensures Durable Long Life Wheels, 2 Full Sheets Of Fiberglass For Durability & Safety, For Fast Cutting In All Types Of Ferrous & Stainless Steel Metals.