Adjustable from 4.5-9 psi for precise fuel pressure adjustments. Constructed of billet aluminum with a black anodized base and clear anodize top for good looks. Used in systems where a return line is not needed. Use with electric or mechanical pumps. One 3/8″ NPT inlet and two 3/8″ NPT outlets. 1/8 NPT gauge port. Comparable and interchangeable with popular Holley® 12-704 regulator. Holley® Billet Fuel Pressure Regulators are part of a complete line of fuel system products from Holley®. They are precision machined from 6061-T6 billet aluminum for strength and durability. They feature a black bright dip anodized body and a clear bright dip anodized top for corrosion resistance and good looks. The Holley 12-843 fuel pressure regulator features (1) -10 AN O-ring inlet, (2) -8 AN O-ring outlets.