Mil-Ram’s RS485/4-20mA smarter 3- and 4-wire transmitter – Tox-Array 2100 uses the company’s no-false-alarms, chemically selective, toxic, LEL and O2 patented sensors for gas detection. Self-calibration adjusts span monthly based on life curve. Auto gas calibration is done in two minutes. Offsite sensor calibration allows sensor replacement in the field without recalibration. Mil-Ram Technology Inc., Fremont, CA.www.mil-ram.com