Fuel, oil or transmission pressure or engine vacuum.

Features

• Digital pressure and vacuum measurements in a single module.
• Measures HVAC/R, hydraulic and pneumatic pressures to 350 psig/2413 kPa (usable to 500 psig).
• Measures to 29.9 in Hg/76 cm Hg vacuum
  (not intended for measuring microns of vacuum).
• Compatible with most popular digital multimeters.