Proprietary SUBSALVE USA Plunger Dump Valve allows air control with a push of a button at the top of the bag and a lanyard at the bottom—vent air from above, beside, or below the lifting bag to achieve desired ascent rate. 1/4″ NPT inflation port for remote filling, multiple bag manifolding, or to install optional stainless steel quick disconnect. Ready for immediate use—factory-equipped with all necessary hardware