It is a clenched fist with the thumb crossed over the folded in fingers. The fist is being held up in the air, and there is a line drawn above the knuckles of the fist that has a peak over the index, middle, and little fingers.
Related to Action Icon
Related icons are the icons with matching tags, as well as all cinema icons. All icons are in the same flat style. You can either download free PNG icons or buy SVG vectors