The FIX-A-TAP Tap tool kit contains all the tools needed to replace your Donson taps. The hex key is the required tool to tighten or loosen. This pack also contains a button spanner, consisting of a hole at the end of a metal bar upon which a nut can be turned with a screwdriver, and a handle hex key, consisting of a long rod that fits directly into an SAE standard 1/2-inch drive; sometimes called an "open spanner." This tool is used to remove or install handles, spouts, and aerators, as well as lift mechanisms. Difficulty loosening or tightening your mixer tap The FIX-A-TAP spanner tap type C is designed to tighten and loosen mixer taps| This handy kit comes with hex allen key sizes 23mm & 29mm, spanner and button spanner| Made to suit Aqualine, Caroma and Raymor (early models)