Slice® products are made with a high-tech ceramic called zirconium oxide. Safer than metal blades. Up to 11X longer lasting than steel. 4 blades/pack, 6 packs/box, 8 boxes per master case, total of 48 packs per master case). Minimum order of 6 Packs. Priced per each.Use only with: Craft Knife (#2110548, #2110589), Scalpel (#2110568), Precision Knife (#2110580), Seam Ripper (#2110596, #2110597)