MILLSTEPS OPEP Breathing Device - Mucus Clearance & Lung Expansion Exerciser for Respiratory HealthAdvanced OPEP Technology for Better Breathing Experience the power of Oscillating Positive Expiratory Pressure (OPEP) therapy with this innovative breathing device designed to clear mucus, expand lung capacity, and improve overall respiratory function naturally. Key Benefits: Effective Mucus Clearance OPEP technology creates vibrations that loosen and mobilize mucus from airways for easier expulsion Expands Lung Capacity Positive expiratory pressure