GASCO 17L-50-20, Carbon Monoxide 20 ppm, Balance Air, Calibration Gas, 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

17L-50-20 is equal to new GASCO Airgas Part number X02AI99CP171988 

GASCO 17l-50-20 Carbon Monoxide Calibration Gas also known as CO Cal Gas, is used for the Calibration and Maintenance of Gas Detectors and Sensors. All of our GASCO Calibration Gas Cylinders ship with a Certificate of Analysis (COA). GASCO Calibration Gas meets or exceeds the requirements of the Original Gas Detection Equipment Manufactures Specifications. GASCO Calibration Gas is National Institute of Standards and Technology (NIST) Traceable, GASCO Calibration Gas is Made in the USA, and produced using an ISO 9001:2008 certified process.