R-125 Refrigerant Calibration Gas in Nitrogen contained in a 600 Liter Aluminum Disposable Cylinder, For Use with Any and All Gas Detectors, Cylinder Connection: TBD Gas Specific, 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