This breathing trainer can expand lung capacity and increase the endurance of the body. It is small and portable, comfortable to use, and has adjustable breathing resistance.Features: Breathing Exercise: The breathing exercise device challenges yourself for better workouts and overall stamina. Expanding Lung Capacity: Helps to expand and improve your lung capacity without having to do a lot of cardio and risk burning calories.Adjustable resistance dial: The adjustable resistance dial can adjust breathing resistance, adjust the intensity according to user needs, and respond to various training needs. Small and Portable: The Lung Breathing Trainer is very compact. With thisdevice, you can perform your daily training wherever you are. For example, breathing exercises can be performed while running.PREMIUM MATERIAL: Made of silicone, the breathing trainer is practical and has a long service life, making it more comfortable to use.Color as shownSize: 5*10*3cmQuantity delivered: 2 piecesWarm prompt:1.As different measuring methods,it will occur 1-3 cm deviation about the items,please ensure that it is okay for you before ordering.2. Because of different monitors and lamplight, the picture may not reflect the actual color of the item, really thank you for your kind understanding3. Only the above package contents, excluding other products.