Calibration Gas Gas Name Methane Nitrogen Gas Mixture 25 Percent Methane Balance Nitrogen Background Gas Nitrogen Cylinder Capacity 17L Cylinder Material Steel For Use With Any and All OEM Gas Detectors Connection Size CGA 600 Max Pressure 240 psi Cylinder Dia 2-9/10 In. Cylinder Height 10-3/4 In. Accuracy +/-5 Percent Calibration Certificate NIST