Disk type check valves are produced in four sizes: 10-32, 1/8" NPT, 1/4" NPT and 3/8" NPT. They are available in both brass and stainless steel and are suitable for use with liquids or gases. Free flow occurs in one direction only; reverse flow is prevented. Fixed flow controls are a parallel arrangement of a disk check valve and a precision orifice. Free flow occurs in one direction and metered flow occurs in the opposite direction. Suitable for both liquids and gases the fixed flow controls are available in brass or stainless steel.