Aeromotive Pro Stock 4-port regulators combine the finest CNC-machined titanium, stainless steel, and billet aluminum with a "state-of-the-art" regulating mechanism. These regulators can handle any fuel, while performing more quickly and efficiently than anything else on the market. Developed with and for Pro Stock racers in NHRA and IHRA competition, and these regulators are designed for use with Aeromotive A2000 fuel pumps.