Description: This exersice trainer was designed with bi-directional adjustable resistance dials, it can improve muscle strength and airflow, and match your strength and allow beginners and pros to set the exact challenge as needed and keep progressing, while it's easy to use and allows you effortlessly adjust the resistance level without interrupting the exercise process, is ideal for the elderly, individuals involved in sports or physical activities, swimmers, musicians. With compact design, the exercise devise is portable for you to train anytime, anywhere. Advantages: Bi-directional adjustable resistance dials Comes with 1 replacement mouthpiece Train anytime and anywhere Detachable & washable Food-grade materials Compact & portable Easy to use Built to last Benifits: Strengthen Endurance Enhance Overall Performance Improve muscle strength and airflow  Target Audience: Beginners or pros, the elderly or individuals involved in sports or physical activities, swimmers, musicians or the average person can exercise with this trainer at home, office, or gym, etc.  Packing List: 1 x Exercise Trainer 1 x Replacement Mouthpiece 1 x User Manual