ACQUITY I-Class SM-FTN Performance Maint. Kit,2890 Back Catalog number: CTS-21240 Availability: In the manufacturer's stock Price on request - + Recommended 11-2529 Screw, Comp., 10-32, 304SS, (Gold-Plated), 10/pk Price on request CTS-10984 Sparge Diffuser Price on request 11-1599 Check Valve Assembly, Outlet Price on request