Respirometer 3 Ball Lung Exerciser Respiratory Exerciser Spirometer Compact, high quality break-resistant plastic Deep Breathing Exerciser for comprehensive respiratory fitness from 600cc/sec to 1200 cc/ sec Helps achieve optimum lung capacity and restoring disrupted breathing patterns Specially designed with 3 stage chambers to provide more efficient exercise to patient at a step up basis USE: Place the device at mouth level, exhale normally before inhaling., Inhale thoroughly until lifting the three balls (if, possible), Hold inspiration as long as possible., Remove the mouthpiece and exhale., Repeat the process