A Viton seal replacement kit (P/N 5131V) for your in-service UV-5 series valves).
Since January 2001, all EECO valves have been manufactured with Viton seals. If you are replacing any of the major components listed on this page (which are supplied with Viton seals) in an EECO valve manufactuered prior to January 2001, EECO recommends that you also replace the older valve seals in the remainder of the valve with the newer Viton seals.