To protect the aircraft from excess vacuum, a vacuum breaker is added to the nozzle. Acting like a reverse of a pressure relief valve, this small device helps to avoid excessive vacuum on the aircraft during defueling.

The GTP-9365 vacuum breaker is made with a 3/8” NPT male thread to fit almost any underwing nozzle but can also be added to the piping. 100% made in the USA, stainless steel with Viton seal.