I own an CircuPool Rj 20 (RJ20NR) that I purchased from your company on 6/5/2017 order# DSP-31637. I am looking for a replacement cell and wanted to male sure that I order the correct replacement. Is the RJ20C-RC-4Y the direct correct replacement for the housing I have? Thank you in advance for your reply. (CircuPool RJ20/AG16 Classic Replacement Cell (Electrode Only))