Product & Specifications:BOOST YOUR STAMINA: Take your workouts to the next level with our breathing resistance trainer. By incorporating our pulmonary exerciser into your daily routine, you can improve your breathing and witness a gradual increase in your stamina and performance over time.UPGRADE YOUR LUNG CAPACITY & TONE YOUR ABS: Our o2 lung trainer not only helps you tone your core muscles but also enhances your oxygen intake and breath-holding abilities. Say goodbye to exhausting cardio exercises and embrace a targeted approach that improves both your lung capacity and abdominal strength.ENHANCE YOUR OVERALL PERFORMANCE: Strengthen your respiratory muscles and abs with our breathing and lung exerciser device, ultimately enhancing your overall performance. By improving your breath endurance, you'll notice a positive impact on your athletic abilities and daily activities.HOW TO USE FOR EXHALATION: You always breathe through your mouth, meaning through the restriction. Exhalation uses diaphragm & abs exertion to push air out. Find resistance level where exhale finishes at the same time as you get impulse to inhale. Repeat several times, rest, repeat again, rest, repeat again. Repeat 3-4 times/week. Enjoy the bonus of toning abs muscles while breathing better!Specifications:Product Name: Breathing TrainerSize: about 5*10cm/1.97*3.94inchMaterial: Silicone, ABSWeight: about 68gUse: Aerobic exercisePacking List:1 * Lung Capacity Exerciser DeviceNotes:1. Due to the lighting effects and photographing angles, there is a color difference in the product, please understand.2. Due to manual measurement, there is a tolerance in the product size.