This PYREX® gas dispersion tube with fritted disc has a coarse porosity (40 to 60µm) fritted disc at an angle of 15° and are used to disperse or scrub gas in liquids. This permits the small gas bubbles to rise from the disc surface without excessive formation of large bubbles. Its performance is comparable to that of a horizontal disc. These tubes can be used in test tubes or flasks since a large opening is not required. Dimensions: (H x Stem O.D.) 250 x 6mm. Disc Diameter.: 40mm. Porosity: Coarse. Material: Borosilicate Glass Code 7740. Corning® #: 39530-40C.