PU-4/6/8/10/12/14/16 one-tuch fittings APPLICATIONS: *One touch type connection tool for air pressure piping. *Various uses depending on the user's environment in limited spaces. Features: *One action inserts the tube to release and connect easily. *The PC type has interior and exterior hexagonal shapes for efficient piping *The main body of the PL and PT types is a rotating structure for efficient piping. *The screw section has O-ring, or Teflon coated