The X-Mach watch from Hamilton measures mach speeds. Period. Not much else you need from a watch, right? It does so by calibrating the pressure altitude (PA) and air speed (CAS). I guess it goes more based on their description, “This transforms the timepiece into a stunning portable Machmeter. For wearers with their feet firmly on the ground, the Hamilton Khaki X-Mach watches increase the exhilaration factor with dynamic, sporty design. Aviation-inspired style elements include wing-shaped metal and carbon-fiber surrounds to protect the crowns, as well as nostalgic flying-jacket style stitching and studs on the bracelet.” Available for under 1700$US.
More views of the Hamilton Khaki X-Mach Watch after the jump.