Product Details:

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.
Blade can be sharpened or replaced.