Rotor Seal, 2-Groove Back Catalog number: CTS-21163 Availability: In the manufacturer's stock Price on request - + Recommended 11-2891 PTFE Diaphragm, 2/pk Price on request CTS-A11336-02 Cartridge, Intelligent Valve, 2/pk Price on request CTS-21089 Needle Seal (For pH 1-14, for operation up to 130 Price on request