GASCO Precision Calibration Gas 409-17 Mixture 50 PPM Carbon Monoxide, 25 PPM Hydrogen Sulfide, 2.5% Methane (50% LEL), 17% Oxygen, Balance Nitrogen in a 900 Liter ecosmart Cylinder, Certification NIST, Made, in the USA |
GASCO Calibration Gas is ISO 9001 Certified.