FILAMATIC Type K Y U & KFU Filling Units Capacities: 0.3mL to 1100mL KYU and KFU: Used with corrosive chemicals and metal sensitive liquids such as acids, reagents, etc. Consists of a heavy wall, precision bore glass cylinder with Kel-F or Kynar piston and valve housings. Comes standard with "O" ring piston seals and Duck-Bill valving. Also available with ceramic ball check valves. Piston head, cylinder head and valve casings fabricated from Kel-F for type KFU Filling Units or Kynar for type KYU Filling Units. NATIONAL INSTRUMENT, L.L.C. Specialists in Liquid Filling Systems Liquid Product Duck-Bill valves are standard with Type KYU/KFU Filling Units. Optional Non-Metallic Spring Ball Check valving available. Duck-Bill valving provides nearly zero wear. They are ideal to use with shear sensitive products.