Check the listing for details. Erie Water Softener Injector Kit. Color: Red, Condition: Open box. Listed at 35.00 USD. Erie 541 Water Treatment valves have been a popular and reliable water softener valves for many years. I no longer service Erie valves therefore I am selling part of my remaining inventory. I have 3 complete injector sets which include the injector disc, injector gasket and injector screen. There were several injector sizes determined by the width of your resin tank. You can see the list below. I only have #3 disc which would be for a 9-10 inch tank. All parts are brand new but took them out of the bag to take the pictures. These are obsolete parts and very difficult to find. # 1 Disc = 13 inch tank diameter - Obsolete # 2 Disc = 10 - 12 inch tank diameter - Obsolete# 3 Disc = 9 - 10 inch tank diameter - Obsolete# 4 Disc = 8 - 9 inch tank diameter# 5 Disc = 6 - 7 inch tank diameter