High Quality Stainless Steel Blades to Resist Rust and for Longer Life. Permits Quick and Accurate Measuring of the most Popular Weld Fillet Sizes in Inch and Metric: 1/8" - I" (3.2 - 25.4 mm. For Inspection of Concave or Convex Fillet Welds. Blades are Deburred for Fine and Smooth Edges. All Sizes and Numerals are Laser etched into the Surface for Clarity and Easier Reading. Set of Seven Blades comes in a Handy, Vinyl Pocket Case with Snap Lock.