The CI-340 Handheld Photosynthesis System is a portable, single-handed tool that measures photosynthesis, respiration, transpiration, stomatal conductance, PAR and internal CO­2. Light-weight and durable, the CI-340 was designed for field use. The optional accessory modules allow researchers to control CO2, H2O, temperature, light intensity, and measure chlorophyll fluorescence, while the ten different customized chambers accommodate any leaf size, including conifer needles and cacti. Direct chamber connection to the CO2/H2O gas analyzer reduces measurement delay and enables rapid measurement of gas exchange with minimal delays.