The manufacturers recommend certain glass cutters for certain hardnesses of glass. The wheels are honed to different degrees of sharpness for this purpose. Most of the cutters are also available both with a straight ended handle, and with a handle with a steel ball on the end for tapping along the underside of the glass to encourage the cut to run. In addition to those differences, there is also a difference in the durability of the cutter, depending upon the material used in the manufacture of the wheel. The standard steel wheel cutter is a fine tool, but a carbide steel wheel cutter is an even finer tool, and will last up to five times longer in normal use. Here is how our cutters fit into this scheme.