Pipeknife EZD Glazing Tool (Pizza Cutter) is meant to assist in de-glazing glass panels that are embedded into flexible materials. For use with silicone, butyl or foam tapes, and other materials that stay flexible over time - DO NOT use with glazing putting or materials that harden over time. Built-in hand guard protects knuckles and serves as a guide. Simply slip the blade into the glazing pocket, and cut along the glass panel. The blade can be sharpened when dull and can be easily replaced. Includes: (1) Pipeknife EZD DeGlazing Tool (Pizza Cutter) and (1) Extra Replacement Blade