Raceworks Fuel Pressure Regulators are machined from high grade 6061-T6 Billet aluminium. These regulators are an ideal upgrade to your fuel system whether it be a flow through or dead head system and will support up to 1000hp. All regulators come with 1/8″ NPT gauge and boost/vacuum reference ports, compatible with all known fuels and are fully adjustable with a rising rate of 1:1. Brackets and screws supplied.EFI 700HP 3port – FPR-501BKSpecificationsPart Number2 x AN-6 Inlets, AN -6 Return, 1/8″ NPT Gauge Port, Operating Pressure 40 – 75PSI, Adjustable, 1:1 Rising rate, Compatible with All FuelsFPR-501BK EFI 800HP 3port – FPR-500BKSpecificationsPart Number2 x AN-10 Inlets, AN -6 Return, 1/8″ NPT Gauge Port, Operating Pressure 40 – 75PSI, Adjustable, 1:1 Rising rate, Compatable with All FuelsFPR-500BK