S104 Differential O2 Analyzer (DOX) is the world’s only patented differential oxygen analyzer with a resolution of ± 1 ppm O2 against a background of air. With the S104 DOX, researchers can measure real-time rates of respiratory oxygen consumption from tiny insects and photosynthetic oxygen production from a single intact leaf. The S104 Differential O2 Analyzer has the greatest dynamic range of any gas analyzer on the market and on a lower resolution setting it can measure O2 exchange in larger animals, even Human.