Abstract: A device (1) for effecting automatic nitrogen filling, or nitrogen-for-air substitution, for the simultaneous inflation/deflation of a plurality of vehicle tires, comprising multiple controllers (17) corresponding to the number of tires to be inflated/deflated, each having an individual display (8), a pressure sensor (9), an inflation valve (4) and a deflation valve (11), whereby multiple vehicle tires may be inflated/deflated simultaneously, with user input interfaces (10) for pressure setting adjustments.