Calibration Gas Gas Name Carbon Monoxide Methane Hydrogen Sulfide Oxygen Nitrogen Gas Mixture 100 PPM Carbon Monoxide 25 PPM Hydrogen Sulfide 2.5 Percent Methane (50 Percent LEL) Balance Air Background Gas Air Cylinder Capacity 44L Cylinder Material Aluminum Alloy For Use With Any and All OEM Gas Detectors Connection Size C-10 Max Pressure 825 psi Cylinder Dia 2-9/10 In. Cylinder Height 10-1/2 In. Accuracy +/-5 Percent Calibration Certificate NIST