Calibration Gas Gas Name Propylene Air Gas Mixture 1 Percent Propylene (50 Percent LEL) Balance Air Background Gas Air Cylinder Capacity 103L Cylinder Material Steel For Use With Any and All OEM Gas Detectors Connection Size C-10 (5/8 in UNF) Max Pressure 1000 psi Cylinder Dia 3-21/64 In. Cylinder Height 13-2/3 In. Accuracy +/-5 Percent Calibration Certificate NIST