This is the cutter against which all other cutters are compared! They're comfortable to hold and easy to use. Each cutter is self-oiling using a unique valve system so oil doesn't get all over the place. The free rolling wheel creates a consistent score line. The wheel is made of durable carbide steel and will out-last normal glass cutters by 25 times!! Simply the best! Heads are replaceable. Measures about seven inches long. Unfilled.