Mr expertgasman are you implying that somebody would actually try to rotate the unhooked rad' before "cracking" loosening the valve coupling nuts. There are a million ways for a million different people. one obvious one is to angle the rad' and insert a 15mm iso valve for the easy task of draining the rad or "extracting the urine" my gizmo was only really for making bleeding less messy and more effective way of relieving any crud out of the top of the rad. But with all the "HELPFUL COMMENTS" it would appear that this is another British world beater destined for the bin.
