Fuel Pressure Gauges by Fuelab1.5 inch Fuel Pressure Gauges for EFI and Carbureted Applications. For reference use on Regulators or Fuel Rails with Gauge Ports. Not for use in Passenger or Driver’s Compartments FeaturesPressure Range Options for EFI/Carbureted ApplicationsBlack Casing1.5 Inch Diameter White Face, with Black Text1/8-NPT Direct MountFor reference use on Regulators or Fuel Rails with Gauge Ports PLEASE NOTEFor reference use on Regulators or Fuel Rails with Gauge Ports. Not for use in Passenger or Driver’s Compartments ApplicationsUniversal What's In The Box?1 - Fuel Pressure GaugeNecessary.