This icon is a part of a collection of Zniżka flat icons produced by Icons8. Icons follow the guidelines of iOS, Windows, and Android and are designed by a single designer, guaranteeing the consistent quality. Both PNG and vector are available.
It’s a circular shape with triangular points on all sides. In the middle there is percentage symbol- a slanted line starting from the bottom left and going to the top right, with two zeros on either side of it.