Feature 1Respiratory Muscle Training: Lung exerciser device works by creating resistance when you breathe, effectively improving your respiratory muscle. 2Multifunction: Breathing lung exerciser can reduce breathing difficulties, improve exercise performance, speed recovery and improve overall health. 3Increase Lung Capacity: Integrated breathing training device, which can effectively improve lung function and prevent respiratory diseases. 4Portable: Respiratory muscle training device is suitable for people other than patients or professional athletes, which is small in size for easy to carry. 5Acrylic Stainless Steel: Handheld breathing exerciser is made of acrylic and stainless steel, safe and sturdy, which allow you can use it at ease.Item Type: Breathing ExerciserMaterial: Medical Acrylic, Stainless SteelSize: Approx. 7 x 4 x 8cm / 2.8 x 1.6 x 3.1in .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }Package List1 x Breathing Exerciser1 x Manual