Calibration Gas Gas Name Carbon Monoxide Hydrogen Sulfide Methane Oxygen Nitrogen Gas Mixture 35 PPM Carbon Monoxide 10 PPM Hydrogen Sulfide 0.14 Percent Pentane (10 Percent LEL) 18 Percent Oxygen Balance Nitrogen Background Gas Nitrogen Cylinder Capacity 74L Cylinder Material Aluminum For Use With Any and All OEM Gas Detectors Connection Size C-10 (5/8 in UNF) Max Pressure 500 psi Cylinder Dia 4-1/4 In. Cylinder Height 14-1/4 In. Accuracy +/-5 Percent