This item is similar to the CG-1820, but with an extra coarse fritted glass dispersion tube to enhance absorption by the trapping liquid. The impinger bottle is graduated from 5 to 30 mL in 5 mL subdivisions. The complete set includes the bottle and fritted glass stopper. The bottle is also available separately; see item # CG-1820.
Details on EPA Method 6, "Determination Of Sulfur Dioxide Emissions From Stationary Sources" is available from the EPA. Note that the test protocol uses one midget bubbler and 3 midget impingers in series, although substitutions may be made.