This tool is nothing more than a chunk of 1" hex bar, but it is far cheaper than a 1" Allen wrench - if you can even find one (*hint*- McMaster-Carr).  If you have this tool, you can use a 1" wrench or socket to easily remove the plug in the end of your ACV.  This is for all RR363 cars - Shadow I's, II's and derivatives.  Not for mineral oil cars with throwaway spheres.