Wheeler-Rex 69012 Glass Tube Cutter
Price 41.25 USD
For .25-Inch thru .75-Inch (6?18mm) O.D. gauge glass, laboratory glass, and porcelain tube * Small enough to carry in your pocket and almost as simple to use as a pair of pliers * Just wrap the chain around the tube, and hook the nearest chain pin in the jaw * then a quick twist of the wrist, a slight squeeze of the handles, and pop