The PAB Model GC-1 Glass Chipper is a dual-ended tool that accommodates 1/8 inch glass on one end and 1/4 inch glass on the other. All PAB glass chippers are fixed-adjustment tools, factory calibrated to accommodate a particular thickness of glass.
It has been designed to provide repeatable chip shape and edge smoothness and is virtually maintenance free. Constructed of lightweight aluminum and carbon steel, these tools have been engineered to insure years of consistent performance and durability.
Here is a video explaining how it works.