Those are commonly seen used on the military space heaters where a constant flow is necessary. They are attached to Jerry cans that are then turned upside down and placed on stand. It's really not intended to be used with any genset that has an auxiliary fuel pump that pumps its own fuel out of a Scepter Jerry can or 55 Gal drum. For that you would use this instead: https://www.steelsoldiers.com/showthread.php?171024-Generator-AUX-fuel-connections.
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