Short answer: Yes. A fiber laser can engrave most polymers used on firearms, including PMags, Glock and Sig frames, and many aftermarket grips. The key is controlling heat: polymer melts and bubbles if you hit it like steel. Our standard Edge 50W marking presets for Glock frames, Sig frames, and PMags each run a single pass at 24 to 42% power. Test on a scrap or hidden spot first, and run fume extraction every time. Below are our actual starting presets and how to get clean, consistent marks on the polymer parts gun shops see most.