A gauge has been developed that is particularly suited for measuring transient gas pressures (e.g., gas bursts expanding in vacuum). A commercial subminiature pentode has been used in a suitable circuit for this purpose. Calibration curves for helium, nitrogen, neon, argon, krypton, and xenon at room temperature are given in the 1 to 400 &mgr; Hg range. The features of this gauge are its small size, short risetime, and simple construction and installation. The serious disadvantage is its short lifetime, about 3 weeks of continuous use, mainly due to filament failure.