Calibration Gas Gas Name Carbon Monoxide Methane Hydrogen Sulfide Oxygen Nitrogen Gas Mixture 300 PPM Carbon Monoxide 10 PPM Hydrogen Sulfide 2.5 Percent Methane (50 Percent LEL) 15 Percent Oxygen Balance Nitrogen Background Gas Nitrogen Cylinder Capacity 34L Cylinder Material Aluminum For Use With Any and All OEM Gas Detectors Connection Size C-10 Max Pressure 500 psi Cylinder Dia 3-1/8 In. Cylinder Height 10-3/4 In. Accuracy +/-5 Percent Calibration Certificate NIST