The SPM-A spirometer from Contec is a had-held equipment used for checking lung conditions. It has an infrared interruption mode that is used for measuring FVC (forced vital capacity), VC (vital capacity) and MV (maximal voluntary ventilation). It also analyzes and displays 32 parameters and the optimal value of the measurements. It also displays respiration waveforms, flow-volume loop and volume-time curve charts in real time. To ensure that the tests done are accurate, it comes with a calibration function.