The inBreathe peak flow meter is an intelligent, easy-to-use instrument that enables you or your child to measure lung function. It can detect internationally accepted asthma indicators: PEF (peak expiratory flow) and FEV1 (forced expiratory volume in the first second), which are key indicators for assessing lung function. The PEF value is visually expressed in three colors: green, yellow and red. Through the PEF signal management method, it can help to evaluate the effectiveness of asthma medications and measure the level of asthma control. The inBreath peak flow meter can automatically record real-time data when used in combination with an app.