(A) The Adjustable knob controls whether the Drum Storm unit creates a vacuum within the drum OR a pressure to empty the drum.
(B) Compressed air flows through the 1/4" NPTM inlet and into the stainless steel drum pump unit.
(C) The liquid enters the drum through a tube assembly that is threaded into the large drum hold. A 90 degree quick release elbow connects the tube assembly to the vacuum hose!