This is the breathing device that strengthens the respiratory system and builds endurance for improved workouts and athletic performance. In endurance mode, ideal for marathon training or long-distance walkers, exercisers manually select a difficulty level and inhale or exhale as long as possible. The unit registers the force of the breath and tracks how many seconds the exerciser met or surpassed the target volume. In strength mode, designed to train the body for quick bursts of activity, breathers exhale or inhale forcefully to hit their target air volume within two seconds. The LCD screen shows how long an endurance exercise lasted and how much effort is exerted via a 1-7 scale so users can easily set new performance goals and monitor progress. Five included attachments provide different levels of airflow restriction, allowing users to progressively increase the difficulty of workouts. The built-in memory stores scores for the last 30 exercises, shows daily, weekly, or monthly scores, and averages results for inhaling and exhaling in endurance or strength modes. Includes two AA batteries. 6" H x 3" W x 3" L. (6 oz.)