SpiroPower®pulmonary function testing transducer is applied the unique ultrasonic measurement ( High-sensitivity, low-resistance ) technology which makes it can simultaneously measures flow and gas density providing all the necessary information about the volume and gas exchange from each measurement accurately .At the same time, the possibility of airway resistance and cross-infection is overcome，An Excellent PFT Device For low tidal air volume, low vital capacity, high respiratory frequency and uncoordinated patient