CO2 detecting tube 1.detect oxygen 2.low cost 3.custom-made. 1.We are one of the leading gas detecting tube and ... price in China. 2.Our company specializes in producing colorimetric gas detection tube. All kinds of tubes have been granted the ... can meet requirement of different customers.4.Tube Type: CO,CO2,H2O,H2S,NH3,PH3,SO2,C4H10,CH3Br,C2H3CL, CL2, HCN ...