X-ACTO X616 100pc X-Life No 16 Scoring Knife Blades. X-Life Blades are made from the highest quality carbon steel, rigidly tested for hardness, and manufactured to the most stringent specifications. They are oxidized to resist rust and increase durability. Based on independent tests, the X-Life blades show a 30 percent sharper edge and have 54 percent longer life than competitive blades. For delicate stenciling, cutting, or scoring. Paper, plastic, balsa, and decals. Offset Blades for accuracy. Fits 1/4 inch Type A X-ACTO or Excel Handles. Packaging may vary.