Iron Neck Pro 3.0 is the premium product from the folks at Iron Neck and the world's most versatile neck strengthening device. With the variable friction dial, you can adjust the level of rotational friction applied when turning your head. The result? Athletes and patients can adapt any form of neck training to meet a number of training goals. Rehabbing neck injuries can be done safely under little or no rotational resistance, while athletes can build strength by applying more friction with the variable friction dial.