portable CO gas detector tube 1.detect carbon monoxide 2.used in ... .custom-made. 1.We are one of the leading gas detecting tube and instruments supplier in China mainland. We ... in China. 2.Our company specializes in producing colorimetric gas detection tube. All kinds of tubes have been granted ... meet requirement of different customers.4.Tube Type: CO,CO2,H2O,H2S,NH3,PH3,SO2,C4H10,CH3Br,C2H3CL, CL2, ...