RKI 81-0084RK-01 equivalent by GASCO R134A Calibration Gas 2000 PPM Balance Air contained in a 17 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 AIR CONDITIONING EQUIPMENT