OMRON light Personal Peak Flow Meter is used for accurate monitoring of Peak Expiratory Flow in L/min. The PFM20 enables an easy, user-friendly therapy management for doctor and patient similarly. The helpful zone-marking (red/yellow/green) allows an individual monitoring of the current state of bronchial obstruction, e.g. in the case of COPD. PEF measurements are part of asthma-management programs.