The Superb Wrench Metal SW-4 fits the following #20 large whole house housings:
The Metal Whole House Water Filter Wrench - SW-4 fits several #20 large whole house water filter housings and is the last water filter wrench you'll ever need. The SW-4 wrench is equipped with a longer handle for better grip and leverage. This large filter housing wrench will not bend, bow or break due to its strong zinc-plated, galvanized steel construction. This whole house filter wrench is labeled with a directional arrow to make sure you turn it in the proper direction.
Metal Whole House Water Filter Wrench - SW-4 specifications: