Qubit Systems manufactures the only gas exchange system, Q-Box NF1LP Nitrogen Fixation Package, for measurements of nitrogenase enzyme activity in nodulated legume roots that evolve H2 gas. H2 gas is a by-product of nitrogenase enzyme found in legume nodules. The system comes with all of the components including the software, data interface and soybean seeds with bacterial innoculum. It is designed for studies of nitrogen fixation in laboratory grown legume plants that evolve H2. This is not a field system.