Holley fuel pressure regulators are designed to precisely control the fuel pressure from the fuel pump to the carburetor, Each Holley fuel pressure regulator is fully adjustable so regulating the fuel pressure to your engines needs is a simple task, The Holley 12-803BP fuel pressure regulator features 3/8″ NPT in/out ports and a 3/8″ NPT return port, These chrome plated push-on brass fittings are the perfect finishing touches for your fuel system, All fittings are male hose barb to male pipe thread. Holley 12-803BP Carbureted Bypass Fuel Pressure Regulator w/Gauge. (1) Holley 12-803BP Carbureted Bypass Fuel Pressure Regulator. (2) Straight Chrome Fitting, 3/8 Inch Hose to 3/8 Inch NPT. (1) Mr Gasket 1561 Fuel Pressure Gauge, 1-1/2 Inch, 0-15 PSI. Holley 12-803BP Carbureted Bypass Fuel Pressure Regulator. Adjustable fuel regulation from 4-1/2 to 9 psi. 3/8 NPT ports (1 in, 1 out, 1 bypass or return). Used in systems with a return line back to the fuel tank. Quieter fuel pump operation. Designed only for carburetor use. Straight Chrome Fitting, 3/8 Inch Hose to 3/8 Inch NPT. Male pipe threads to hose barb ends. 3/8″ Hose to 3/8″ NPT adapter. Fuel line hose connector. Mr Gasket 1561 Fuel Pressure Gauge, 1-1/2 Inch, 0-15 PSI. This conveniently small 1-1/2 gauge will fit almost anywhere. The gauge has 1/2lb increments with a range of 0-15lbs. And has a 1/8 NPT male fitting. Regulator works awesome &####128077. By Jimmy on March 25, 2021. It only came with two fittings, be nice if it came with three for the in out and return line. Speedway Motors is America’s Oldest Speed Shop® and has been a trusted source for specialty rodding and racing products and friendly expert advice for more than 72 years.