With a bi-directional 24-hour GMT bezel, the Spirit Zulu (in both sizing) mirrors the operate set established by well-liked GMTs just like the Tudor Black Bay GMT, the Black Bay Professional, and the Rolex GMT-Grasp II. Principally, you may set the principle time show to indicate native and the 24-hour hand to indicate house time (leaving the bezel in its pure place), or you may alter the 24-hour hand to indicate UTC time after which rotate the bezel to indicate a 3rd time zone (native, UTC, and UTC offset). To place a bow on the specs, the crystal is sapphire, the caseback is closed, the lugs are usually not drilled, the crown screws down, the bezel insert is ceramic (non-lumed, except for the triangle marker), and the water resistance is 100 meters.