Calibration Gas Gas Name Propane Nitrogen Gas Mixture 75 ppm Carbon Monoxide Balance Air Background Gas Air Cylinder Capacity 105L Cylinder Material Aluminum For Use With Any and All OEM Gas Detectors Connection Size C-10 Max Pressure 1200 psi Cylinder Dia 3-13/64 In. Cylinder Height 12-1/2 In. Accuracy +/-2 Percent Calibration Certificate NIST