Mount a Guardair Dual Venturi Vacuum Generating Head on any standard 55 gallon drum for instant, high-performance vacuum capability. Generates 63% more vacuum flow than single venturi units to pick up the heaviest of materials quickly. Powered by compressed air, always dependable and trouble free with no motors or moving parts to wear out, Guardair Dual Venturi Vacuum Generating Heads produce exceptional vacuum lift and vacuum flow while operating quietly and efficiently. Equipped with dual B type venturis. Non-returnable item.