Welcome to visit our official website : http://www.nasalendotracheal.com Contact us:+86-1 5890169579 Email: leo@aileindus .com Three-way valves are commonly used in fluid control systems to redirect the flow of fluids between two different pathways. These valves have three ports: an inlet, an outlet, and a common port. By turning the valve, the flow can be directed from the inlet to either of the two outlet ports, or from one outlet to the other.