The Etching Tool fits in the blade housing unit in the Silhouette brand of electronic cutters (Cameo and Portrait) and the Cricut brand electronic machines EXCEPT for the Cricut Explore (it doesn t fit in those models). It also fits in the KNK (Klic-N-Kut), Pazzles, and Xyron Wishblade. It can be used to engrave and etch many materials, including acrylic, plastic, glass (if your machine allows this), metal and metal clay. Any material used with this tool should sit on the machine s mat and fit under the machine s rollers. For the Silhouette machines, anything less than 0.8mm thick will fit, including metals (copper, bronze, silver, aluminum...) at less than 18 gauge thickness. Ensure the machine you use can accommodate the media you desire before committing to specific media use.