Designed from specifications of ASTM D-2912 for an all glass midget impinger tube used in the Standard Test Method for Oxidant Content of the Atmosphere (Neutral KI).

The impinger consists of a 25 mm O.D. flat-bottom tube with a 24/40 outer joint and graduations in 5 ml increments to 30 ml, fitted to a stopper assembly consisting of a 24/40 adapter with a connection for attaching an air pump, and a 5 mm I.D. inlet tube with a nozzle 1 mm I.D. concentric to the joint and outer tube. Overall height is 170 mm. (ASTM D-2912, D-2914)