• Improve your endurance: This respiratory exercise trainer is ideal for improving your breathing, increasing your endurance, and making you feel better day by day. • High-quality material: Made with high-quality silicone, non-toxic, odorless, harmless, and environmentally friendly. It improves breathability and durability in case of shortness of breath and provides 100% adjustable resistance when inhaling and exhaling. Lightweight and small, it can be easily carried. • Easy to use: The Hypoxia Lung Trainer fits all mouth shapes, sealing perfectly and being comfortable to use. Slowly and deeply inhale through the mouth, hold the air for a few seconds, and slowly exhale until you are almost out of breath. • Enhances body performance: This respiratory exercise device helps reduce buildup caused by body excretion, significantly increases your lung capacity, and strengthens respiratory and abdominal muscles. • Widely used: Ideal for swimming, diving, surfing, running, fitness, travel, and more. It offers different adjustable resistance levels to suit your needs.