Nozzle designed for pump driven fuel systems with a minimum of 15 PSI and a maximum of 43 PSI. A minimum of 15 PSI is required to operate the auto shut-off. Do not use on gravity flow systems. Improper use may cause a hazardous condition. Avoid static hazard. In case of fire do not remove nozzle. No smoking/extinguish all flames. Licensed drivers only. Do not top off. Refer to posted warnings.