Needle Seat, PEEK™, 0.17mm ID Back Catalog number: CTS-21253 Availability: In the manufacturer's stock Price on request - + Recommended CTS-21743 Valve Cartridge, Bio-compatible, NCS/NCP, 2G Price on request CTS-21173 O-Ring (3/16" X1/16", Viton™) Price on request CTS-11286 PM Kit for Isocratic/Quaternary Pump Price on request