This chisel tipped solder iron helps to remove the plastic ball plugs from Canon/HP cartridges. Some of the newer model cartridges have a hard plastic plug that is difficult to remove. This iron is used to melt a hole in the plug, then either a plug remover Part #7067 or a drywall screw is inserted in the hole to pry the plug out. Complete instructions can be found in our hand refill kit #3264.