Check Valve Cartridge, 2/pk Back Catalog number: CTS-10493 Manufacturer: SCIENCIX Availability: 3 weeks Price on request - + Recommended CTS-A11372 Tube Assy, Transducer to Check Valve, I2V Price on request 11-1603 Seal, Wash Price on request CTS-10328 Optics Cover Window Price on request