MIL-STD-810H is a newer revision of the 810 standard (building on 810G) with updated test methodologies and profiles. It covers the same areas of environmental durability - shock, vibration, temperature extremes, humidity, dust, freeze-thaw cycles, low pressure, solar radiation, and more - with refined procedures. As with the 810G, this is not a uniform certification; what matters is which methods have actually been performed and with what parameters. For rugged watches, it indicates testing according to a more rigorous or up-to-date version of the methods, which is relevant for demanding outdoor use.