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This Schwartz-type drying tube has 14/20 hollow stoppers on both ends. Each stopper has a hole that aligns with the serrated hose connection, allowing the user to shut off the tube or gas flow and permitting storage or re-use of the packed tube without a loss of dessicating ability. The overall height with stoppers is approximately 170 mm and the outer diameter of the tubing is 19 mm.
In typical use, one fills the tube with an appropriate dessicant such as calcium chloride or potassium hydroxide, using a small plug of glass wool at the top of each side to contain dust or particles.