Calibration Gas Gas Name Propane Air Gas Mixture 1.1 Percent Propane (52.3 Percent LEL) Balance Air Background Gas Air Cylinder Capacity 66L Cylinder Material Aluminum Alloy For Use With Any and All OEM Gas Detectors Connection Size C-10 Max Pressure 1200 psi Cylinder Dia 2-9/10 In. Cylinder Height 10-1/2 In. Accuracy +/-5 Percent Calibration Certificate NIST