These Pyyrex® gas washing bottles provide an inexpensive but effective method for washing and drying gases. A 29/42 Standard Taper stopper is used to seal the top to the base. These bottles are a very effective way to humidify carbon dioxide-air mixtures for maintaining high humidity in gassed cell culture incubators. The gas enters the bottle through the top of the central vertical tube, the lower end of which is below the surface of the washing medium. After bubbling through the medium, the gas is removed via the sidearm of the bottle stopper. The Standard Taper stopper incorporates a plain tip tube as the distributor. These bottles have large hexagonal bases for stability. Sidearm tubulations are 10mm O.D.