Quickly Improves Breathing - Get fast results with thanks to our smart original design proven effective by thousands of thrilled customers. It uses an easy adjustment to provide the widest range of inspiratory and expiratory resistance to make lungs stronger. Used by rehab patients, competitive athletes, COPD and many more to make lungs more effective and efficient in pulling in Oxygen and pushing out CO2.* Easy To Use - Simply place mouthpiece in mouth and adjust the single adjustment knob to provide the preferred amount of air resistance. Lets you gradually strengthen lungs. Many people experience quick improvement. Chosen #1 breathing resistance exerciser by the LA Times. Frequently an Amazon Choice. See our thousands of positive customer reviews from real people who insist onfor stronger lungs.* Compact 4" Pocket Size - is just 4" long making it ideal for carrying in your pocket, purse, backpack, or car. We make these extremely durable with heavy duty medical grade silicone that won't rust or break.Designed for a lifetime of highly beneficial daily use.* Helps Lower Blood Pressure & Improve Sleep - A new Harvard study shows strengthening breathing muscles helped many adults naturally lower their blood pressure. Easier breathing and more nourishing oxygen can lead to improved sleep.opens airways into your lungs that have been partially blocked over the years due to natural aging, pollution, poor physical condition, or smoking