R410A Refrigerant Calibration Gas in Nitrogen contained in a 34 Liter Steel Disposable Cylinder, For Use with Any and All Gas Detectors, Cylinder connection CGA 600, Calibration Certificate NIST, Made in the USA, Calibration Refrigerant Gas is intended for use in Calibrating Refrigerant Gas Detection Equipment Only. NOT INTENDED FOR CHARGING Nitrogen CONDITIONING EQUIPMENT