One of the many symbols used in National Socialist Germany. The symbol's design consists of twelve radial sig runes, similar to the symbols employed by the SS in their logo. It first appeared in Germany as a design element in a castle at Wewelsburg remodeled and expanded by the head of the SS, Heinrich Himmler, which he intended to be a center for the SS.
More info: https://en.wikipedia.org/wiki/Black_Sun_(symbol)
The following tags implicate this tag: black_sun_tattoo (learn more).