Abstract: A hand held mechanism that can be applied to a conventional tire inflation valve on a vehicle tire to facilitate a tire deflation operation. The mechanism includes a rod-like element that automatically engages a tire check valve to open said valve for tire venting purposes. The mechanism also includes a hollow tubular called wall structure adapted to receive the sensing head of a conventional pressure gage, whereby the progress of the tire-deflation operation can be ascertained, as necessary to properly terminate the operation at a desired tire pressure. Mechanisms of the described type can be utilized on all wheels of a multi-wheeled vehicle to permit simultaneously deflation of all vehicle tires, thereby greatly reducing the time required to achieve a total tire deflation operation.