It is shaped like a hexagram, which is made up of two equilateral triangles. The hexagram has been used as a sign of Judaism since the 17th century, with precedents dating back to the 14th to 16th centuries in Central Europe, where the Shield of David was partly used on Jewish flags alongside the Seal of Solomon (the hexagram). Since antiquity, the hexagram has appeared in Jewish contexts on occasion, presumably as a decorative motif. A stone carrying a hexagram from the arch of a 3-4th-century synagogue in the Galilee, for example, can be found in Israel.