1-3/8" HSS Blade Imperial Blades SC415. Best for fiberglass, carbon fiber and sheet metal. For linear and plunge cutting. 1-3/8" width 1in cutting depth. High-speed steel material is rigid, allowing the blade to cut through harder woods and sheet metal up 1mm thick as well as carbon fiber, fiberglass and nails. Ideal for working in corners. Made with the industry's highest quality high speed steel material. SC Arbor fits all Fein Supercut oscillating tools.