Check Valve Cartridge, 2/pk Back Catalog number: CTS-A094 Manufacturer: SCIENCIX Availability: 3 weeks Price on request - + Recommended CTS-A11342 Tube Assembly, Transducer to Check Valve Price on request CTS-21577 PM Kit, G1367E Price on request CTS-10548 Gold Plunger Seal, Analytical Heads Price on request