Discriminator Valves

Discriminator Valves: Use a light weight float that floats up to prevent fuel from going up into the vent line when you fill your vehicle.

Rollover Valves: Use gravity to prevent fuel from going up into the vent line when you roll the vehicle upside down.

Note: Some discriminator valves feature two balls. One is heavy and dense and uses gravity to prevent fuel from going up into the vent line when you roll the vehicle upside down. The other ball is light weight and floats up to prevent fuel from going up into the vent line when you fill your vehicle.