1.SAVE YOUR TRAINING TIME UP TO 50% - By our high altitude mask to create a similar high altitude environment, The mask enforce you to breath deeply, so during same time, the workout efficiency is doubled. 2.BOOST YOUR LUNG CAPACITY & ENDURANCE - By restriction oxygen and create high altitude environment, Our altitude Mask will force you to take full and deepest breaths, so the breaths muscle is highly excised & Your Lung and respiratory system performance will be improved. 3.For ALL LEVEL FITNESS PEOPLE - Our training high altitude mask has two air paths, each path has 4 level adjustable, and two additional soft valves to create up to 24 breathing resistance levels, suitable people from beginner to Pro. 4.SMART ERGONOMIC DESIGN - Our mask is made of finest material and its ergonomic designed, it can fit all face perfectly with adjustable belt, the soft rubber is easy to keep our side air isolated from your face and to avoid slip during train.5.GREAT IDEA FOR GIFT - Luxury gift box packaging, great idea for gift. Only for Fitness NOT for Cornavirus