The Air Systems ASI-2900 Venturi-style pneumatic air blower has a galvanized steel housing and cast aluminum base, and uses compressed air or steam to ventilate vapors and fumes from underground storage tanks or other below-ground locations. It has no moving parts for low maintenance. The housing is made from galvanized steel for corrosion resistance and can be replaced when it shows signs of wear. The base is made from lightweight cast aluminum and comes in standard API (American Petroleum Institute) base sizes. The blower comes with a static grounding lug to dissipate static electricity and prevent accidental ignition of vapors or fumes. It has a built-in steel handle for carrying. The air blower can operate at pressures up to 140 pounds per square inch (psi). Specifications Overall length 44.00 Diameter of housing 13.00 Diameter of base 11.16 Bolt circle diameter 10.28 Base slot 0.43 Intake valve connection 1 NPT Total air flow 2770 cubic feet per minute (cfm) at 50 pound force per square inch gauge (psig), 3340 cfm at 70 psig, 3752 at 90 psig Air consumed 76 cfm at 50 psig, 99 cfm at 70 psig, 127 cfm at 90 psig Weight 22.1 lb. Venturi-style blowers, also known as air horns or eductors, use the principles of the Venturi effect to vent hazardous vapors and fumes from below-ground sources. The base of the blower is connected to the underground tank or source where the fumes and vapors are present, and compressed air or steam is brought into the blower through a nozzle. Its narrow base constricts the compressed air or steam, which increases its velocity as it moves toward the vent at the top of the horn. This decreases the ambient pressure in the horn and creates a partial vacuum, drawing fumes up through the base and out through the vent. Air Systems International manufactures air filtration systems, breathing air compressors, confined space ventilation products, and other safety equipment for industrial, military, and emergency response applications. The company, founded in 1984, is headquartered in Chesapeake, VA, and meets International Organization for Standardization (ISO) 9001 standards for quality.