Check Valve Cartridge, 2/pk Back Catalog number: CTS-10600 Manufacturer: SCIENCIX Availability: 3 weeks Price on request - + Recommended CTS-10686 Needle Seal, Vespel® Price on request CTS-21287 Needle Kit, 15 µL with Needle Seat and Needle Guid Price on request CTS-21171 Rotor Seal, H-Assy, 6 Port 2-Position Price on request