Grasping the face mask of another player while attempting to block or tackle him. In the NFL, the grasping and pulling/twisting must be intentional to be penalized. Under NCAA rules, it is a foul to grasp and twist the face mask. Under high school rules, any grasping of the face mask, any helmet opening, or the chin strap is a foul, though grasping and twisting carries a more severe penalty than "incidental" grasping without any twisting.