JSB Peak flow meter for adults is a home diagnostis and measurement of asthma levels. Peak Flow Meter Adults India can effectively measure your lung strength which can be a vital data for your lungs functioning and can help your pulmonologist understand your lung function and take decision on your medication. Just blow into the mouthpiece and check your reading. Can be used at home by patients or by clinics/hospitals. The JSB peak expiratory flow meter comes with a 1 year warranty.