Introduction: Controlling and preventing symptoms of exacerbations. shortness of breath. cough and mucus in the lungs are important goals of Chronic Obstructive Pulmonary Disease (COPD) treatment. Oscillating Positive Expiratory Pressure (OPEP) devices have been shown to improve clinical results. https://www.nacrack.com/hot-savings-HiBoost-Home-15K-Smart-Link-F20G-5S-IoT-limited-super/