Our #14 metal wrench for water filter housings will be the last wrench you ever need. If you have had trouble getting your housings loose during filter changes or if you have ever broken a plastic wrench, then you need our galvanized water filter wrench. It will not bend, break, or bow. Inside Diameter (not from the tabs) – 4.5″. Half circle style universal, the “Rescue Wrench”, for tight spots and odd housings.