Calibration Gas Gas Name Carbon Dioxide Air Gas Mixture 1.5 Percent Carbon Dioxide Balance Air Background Gas Air Cylinder Capacity 34L Cylinder Material Steel For Use With Any and All OEM Gas Detectors Connection Size CGA 600 Max Pressure 500 psi Cylinder Dia 2-9/10 In. Cylinder Height 10-3/4 In. Accuracy +/-5 Percent Calibration Certificate NIST