Decisive Fitness PH Training Mask, Workout Mask, Running Mask, Breathing Mask, Resistance Mask, Cardio Mask, Endurance Mask, PH Training Mask Size:Face Cut Mask   Workout training mask / fitness mask - for running biking training and fitness, achieve high altitude elevation effects with 4 level air flow regulator [peak resistance] achieve the effects of a high altitude workout efficiency when training, which helps decrease and ; maximizes your workout time 4-level resistance valve system - increase and conditions lung capacity by creating pulmonary resistance simple usage, ultra-lightweight, anatomically designed, non-slip training strap, one size fits most - from 120 to 230 lbs strengthens the diaphragm, trains breathing muscles and improves overall performance in any sport workout training mask - for running biking training and fitness, achieve high altitude elevation effects with 4 level air flow regulator [peak resistance] the aduro sport peak resistance training mask lets you achieve the effects of high altitude training by regulating how much air you breathe in with the 4 level air flow regulator. You can then reduce the amount of training time by getting the same results in a shorter amount of time. You will also increase your lung capacity and will constantly push your training limits to the fullest. Features: achieve the effects of a high altitude workout efficiency when training, which helps decrease and ; maximizes your workout time 4-level resistance valve system - increase and conditions lung capacity by creating pulmonary resistance simple usage, ultra-lightweight, anatomically designed, non-slip training strap strengthens the diaphragm, trains breathing muscles and improves overall performance in any sport one size fits most - from 120 to 230 lbs