In 2004, Harry Winston introduced the “Project Z”, introducing its first watch from the series in the same year was the Z1. The Z4 was the fourth model to be launched in the series in 2007. Featuring a zalium case, a material that is hard, light in weight with a zirconium alloy base, the material is traditionally used in jet engines. With a dual-time function, the second time-zone can be adjusted via a pusher positioned on the left side of the case band with two moon phases for each dial. When one zooms into the center of the watch a small rotating “shuriken” can be noticed indicating that the movement is functioning properly.