Description: Breathing ExerciserDeep Breathing Lung Exercise Device is a breathing trainer which increases lung strength and capacity.High QualityPortable Lung Strengthening Trainer Device is made of premium silicone material, flexible, durable and lightweight.Adjustable ExerciserBreathing Exerciser Trainer is adjustable by manual rotation, great for singers, athlete, pilots, divers, swimmers, etc.Easy To UseHandheld Lung Expansion Training Tool is easy to use, featuring breathing slowly through mouth and as deeply as you can. Wide ApplicationsBreathing Exercise Device is widely suitable for running, jogging, swimming, diving, fitness, biking, etc. Specification: Material: Silicone Size Chart: 5cmx10cmx3cm/1.97inchx3.94inchx1.18inch Package Includes: 1 Breathing Exercise Device Note: Please allow slightly errors due to manual measurement and different monitors.