Feature: 1. Clear Scale: This lung rebreather has a clear scale, which makes training more motivating and more adaptable to the exercise needs of the elderly. 2. Increase Respiratory Strength: Enhance respiratory strength and control performance. Training your anaerobic broadening and push your limits. Increase oxygen intake and maintain endurance. 3. Postoperative Use: Used to help improve the depth and duration of breathing after abdominal or thoracic surgery, to help improve respiratory function, restore lung function, and reduce and prevent postoperative complications. 4. Portable Device: The lung breathing trainer is retractable blowing tube, easy to carry does not take up space. With this device, you can perform your training routine wherever you are. 5. Wide Range of Applications: This product is suitable for strengthening respiratory muscles, increasing lung ventilation, improving coughing ability, helping to remove sputum, reducing surgical complications, preventing pulmonary atelectasis, etc. Specification: Item Type: Breathing Exercise DeviceMaterial: Polystyrene . Package List: 1 x Trainer1 x Bite Mouth1 x Instruction Manual Note: This product is mainly used for deep breathing exercises and tests, but is not a professional spirometer. The scale on the surface of the product is a reference value and for reference only.