Febco FRK 805 805YD 806YD 825 825YD 826YD CR S 4 Part of the RK 805YD 806YD 825YD 826YD Series mainline adatile 2 IN Kit Contents Disc 2 IN Kit Contents Disc Holder Assembly The intended installations are in systems where it is anticipated that the internal pressure exceeds the rated pressure of the system components or for installation downstream of a pressure reducing valve in accordance with ANSI NFPA 13 This kit consists of all silicone rubber parts necessary to repair the check valve of the applicable valve This silicone check valve rubber parts kit includes the parts necessary to repair or replace the check valve silicone rubber parts of a 4 inch reduced pressure zone assembly