58L-421 – CALIBRATION GAS 58L Description Description Calibration Gas 58L Capacity Gas Mixture : Carbon Monoxide CO – 100ppm Hydrogen Sulfide H2S – 25ppm Methane CH4 – 2.5% Volume ( 50% LEL ) Oxygen O2 – 18% Volume Nitrogen N2 – Balance Related products 2001G – DEMAND FLOW REGULATOR QT-XWHM-A-Y-NA Gas Alert Quattro GA24XT- M Gas Alertclip Extreme – CO 70-0.5 – FIXED FLOW REGULATOR 0.5LPM