Refill pack with five premium steel blades designed specifically for TrueControl Knife (sold separately). With razor-sharp edges and piercing tips, these five replacement blades designed for the TrueControl Knife cut through a wide variety of materials, including paper cardstock, thin plastics, canvas, and more. A useful storage cartridge makes it easy and safe to track and dispose of used blades. For use with Cricut TrueControl Knife only (sold separately).