this glass cutter is fixed with tungsten carbide wheel, and widely used in flat glass, stained glass etc for below advantages:

1. Carbide wheel is super, blade is specially processed, make your cutting line near perfect.

2. Handle is special plastic, not easy to break or crack.

3. Metal pontes are made of copper which is more durable and stainless, becose copper is heavier, could knock off the glass easily after cutting.