Harmon Racing 1" Discriminator Valve, RAW Aluminum body. This particular raw version is good for a user that may need to weld to the aluminum body for custom applications.
Similar to a check valve or vent, discriminator valves prevent fuel from traveling up the vent line during filling when the tank is full. Utilizing a float, the valve shuts off air flow when fuel enters the chamber. The valve also operates independently and will close/shut off if overturned regardless if there is fuel in the chamber. Because of it's ability to prevent fuel from traveling up the vent line and out the vehicle these have become popular on vehicles utilizing dry break fill systems and pressurized fill systems. Inlet and outlet requires inner diameter 1.00" hose.
NOTE: Because it is located outside the tank it does not replace the need of a traditional check valve.