The innovative MicroGP is an inexpensive precision Spirometer designed for the family or primary care physician. The MicroGP is the device of choice for COPD and Asthma screening offering a high degree of accuracy with simplicity of operation. Measuring and displaying FEV1/FVC/PEF with percent predicted as well as allowing a direct printout which includes the small airways flow indicators of F50/F25/MEF and the Flow/Volume and Volume/Time curves.