Matheson-Kitagawa precision detector tubes are formulated with high purity chemical reagents which absorb and react with the gas or vapor being measured. The reaction causes a colorimetric stain which varies in length to the concentration of the gas or vapor being measured. The length of stain is normally read directly off a scale printed on each tube. Four types of Matheson-Kitagawa tubes provide the needed flexibility for different gases and sampling conditions.
Don't order more than you will use in the near future. Gas detection tubes have a finite shelf life. MATHESON guarantees the detector tubes you receive will have at least three months of remaining shelf life.