Calibration Gas Gas Name Carbon Monoxide Gas Mixture 500 ppm CO Background Gas Air Cylinder Capacity 103L Cylinder Material Steel For Use With Mfr No 24-7059 Connection Size 5/8 In.-18 UNF threaded collar Max Pressure 1000 psi Cylinder Dia 3-1/2 In. Cylinder Height 13-3/4 In. Accuracy +/-2 Percent Calibration Certificate NIST