Measuring the decay of time using Carnots second law of thermo dynamics. With 35mm diameter Quartz crystal movement and unique 'Galvanic Scale' watch face and magnetic-fastening hatch. The EER Steam-Powered Entropy Calibrator Wristwatch is available in one adjustable size. Pewter, made in England. Ships Separately, No Express Shipping available on this item. Cannot ship outside of the US.