TigerSharp, 2 Pack. This replaceable blade technology means your knife never needs to be sharpened, simply remove the dull blade and slide a fresh one between the guides. Titanium Bonded blades are 3x harder than steel and stay sharper longer. Resists corrosion and adhesives. Includes 2 serrated replacement blades. For use with TigerSharp folding knives #18562, #18563, and #18564.