This 81 pack of safety knife blades are manufactured with the highest quality carbon steel and provide up to three-times longer lasting use. Opening boxes is a breeze with these blades that are constructed with a patented radius tip that helps to prevent product damage and injury when cutting. Easily replace your old blades with ones that don't chip and offer a sharp edge for up to 5,000 feet of cuts. Replacement blades are compatible with all Spec Ops Safety Knives and come in an easy-to-open dispenser. We support our nation's heroes by donating 3% of proceeds to veteran and first responder causes.