QuadraTherm 640i and 780i air flowmeters from Sierra Instruments are available with HART and Profibus DP certifications, giving operators flexible application solutions. Users have easy access to all relevant data available in their flowmeter, allowing them to see where they need to make improvements in their process. They offer accuracy of plus-or-minus 0.5 percent of readings above 50 percent of full scale for flowmeter air measurement and other gases, built-in flow conditioning, multivariable outputs, and qTherm Dial-A-Gas, Dial-A-Pipe and Hazardous Area approvals. They have no-drift sensors, and multivariable outputs, and measurement of all inert and all non-condensing clean gases, and flammable gases (methane, propane, hydrogen and digester gas). The repeatability for mass flow rate is plus-or-minus 0.15 percent. ValidCal Diagnostics validate calibration in the field, and gas accuracy is plus-or-minus 1.8 degree F. 800/866-0200; www.sierrainstruments.com.