A fielder or catcher cannot use his cap, mask or clothing as if it were a glove and touch a ball that is in play. He also cannot throw these items or his glove at the ball, touching it. If he does so, preventing a home run, the home run counts. If he does so and contacts a fair batted ball (or that might become fair), the award is three bases. If the violation is a touched throw or pitch, the runners get two bases.