AUTO METER BOOST/BLOWER PRESSURE METER- Suitable for diesel 4x4- Electrical Or Mechanical (Some Liquid-Filled) And In Four Diameters, These Gauges Are Designed For Pro Racers.- Consist Of The Finest Components For Dependability And Accuracy, And Gauge Faces Offer Ultimate Visibility.- Delivering Precisely The Information That You Need, When You Need It every Time- Assembled And Computer Calibrated By Skilled Technicians To Deliver Unmatched Accuracy And Durability.