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. These tubes are only to be used with the 8014BAK Compressed Breathing Air Analysis Kit.
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.