Wonder Care Breathing Measurement Respiratory Spirometer Lung ExerciserAbout the product Made of good quality materials that last longer. 3 balls Lung Ecerciser inhaling breath measurement system Helps in achieving maximal lung expansion and strengthening cough effort which helps in maintaining clear airways Can be dismantled and cleaned thoroughly helps maintain bronchial hygiene and avoids infection Detailed instructions for Exercising, Calculation of Inspired Volume and Cleaning are provided. Three chambers design