ACQUITY I-Class SM-FTN Performance Maint. Kit,2890 Back Catalog number: CTS-21240 Availability: In the manufacturer's stock Price on request - + Recommended CTS-11092 O-Ring, PTFE Price on request CTS-21463 Check Valve Cartridge, Ceramic, 2/pk Price on request CTS-21147 Inlet Check Valve Price on request