The Dixon 5000AIHD is a 3-way pneumatic air interlock valve featuring a button plunger design for tank trailer applications. This air interlock valve connects to the truck airline system and provides improved safety and reduced operator error during loading and unloading operations. The valve has a 1-inch button plunger, is made from aluminum, and includes a Baylast seal. Furthermore, this is the heavy duty verison of the Dixon's standard brake interlock valve and features high-flow air ports.