Hansatech Instruments Limited
- Manufacturers of oxygen electrodes and chlorophyll fluorescence systems for the measurement of cellular respiration and photosynthesis in the field or laboratory.
- http://www.hansatech-instruments.com/

Apogee
- Products used to measure radiation and leaf temperature, ordering information, and research and development being undertaken.
- http://www.apogee-inst.com/

EARS Plant Photosynthesis Meter
- Specifications and applications of the EARS-PPM, a modulated, saturation pulse chlorophyll fluorometer.
- http://www.ears.nl/ppm/

CID, Inc.
- Manufacturers of portable, photosynthesis analysis systems and miniature spectrometers.
- http://www.cid-inc.com/

Walz
- Producer of sophisticated photosynthesis measuring systems. The product line ranges from PAM Chlorophyll Fluorometers to measuring systems of plant gas exchange for physiological and ecophysiological research.
- http://www.walz.com/

ADC BioScientific
- Manufacturers of instrumentation for measuring photosynthesis, transpiration, chlorophyll fluorescence, sap flow, and gas exchange.
- http://www.adc.co.uk/

Physiological Ecology Equipment Manufacturers
- Links to suppliers of equipment used by ecophysiologists.
- http://www.biology.duke.edu/jackson/ecophys/equipment.htm

PP Systems
- Manufacturer of portable photosynthesis/respiration measurement instrumentation, CO2 and H2O Infrared Gas Analyzers for lab and field, portable spectrometer, and environmental sensors.
- http://www.ppsystems.com/

LI-COR Environmental Research and Analysis Division
- LI-COR Environmental was founded in 1971, and is a leading manufacturer of electronic instrumentation for environmental, agricultural and ecological research.
- http://env.licor.com/

PMS Instrument Company
- Manufacturer of pressure chamber instruments for measuring plant water potential and irrigation scheduling. Contains product information as well as tutorials on using a pressure bomb.
- http://www.pmsinstrument.com/