Aquagraph watch is extremely water resistant and incorporates a helium valve for saturation diving. The TAG Heuer Aquagraph is powered by a highly precise and reliable Swiss selfwinding movement which incorporates a chronograph mechanism. This mechanism, exclusively optimized by the engineers at TAG Heuer, allows central reading of elapsed chronograph minutes, and the operation of the chronograph underwater to the full warranted depth of the watch, making critical underwater time measurement simple and highly legible. Possessed of numerous innovative technical elements, and boasting the uncompromising sporting construction for which TAG Heuer is well known, the Aquagraph watch will satisfy the most stringent professional diving demands.