Plunger Seal and Back Up Ring Back Catalog number: 11-4126 Manufacturer: SCIENCIX Availability: In the manufacturer's stock Price on request - + Recommended CTS-10600 Check Valve Cartridge, 2/pk Price on request CTS-A11095 Check Valve, Double Ball & Seat Price on request CTS-11425 Sapphire Plunger Price on request