The HypAir design is the original Medisoft Pulmonary Function System it has a single circuit subject valve and a small footprint design. It can be built to specification from a wide range of test modules. With choice over diffusion methods, lung volume methods and then many add-on features to offer the most comprehensive test options. The easily adjustable subject valve and arm can be placed at almost any angle and can even take measurements of bed ridden subjects. The trolley mounting of a full system inclusive of computer monitor and printer is unequalled.