They may be purchased off-the-shelf from laboratory suppliers or made from round-bottom flasks or glass tubing by a skilled glassblower.
The side arm contains a valve, usually a greased stopcock, used to control the flask's exposure to a manifold or the atmosphere.
While the flask is connected to the line under a positive pressure of inert gas, the septum can be replaced with other apparatus, for example a reflux condenser.
Schlenk bombs include structurally sound shapes such as round bottoms and heavy walled tubes.
In addition, all Schlenk bombs are designed to withstand the pressure differential created by the ante-chamber when pumping solvents into a glove box.
In some situations, however, Schlenk bombs are less convenient than standard Schlenk flasks: they lack an accessible ground glass joint to attach additional apparatus; the opening provided by plug valves can be difficult to access with a spatula, and it can be much simpler to work with a septum designed to fit a ground glass joint than with a Teflon plug.
The smaller neck includes the threading required for a teflon plug to be screwed in perpendicular to the flask.
Once connected, the plug valve can be partially opened to allow the solvent in the Straus flask to be vacuum transferred to other vessels.
Or, once connected to the line, the neck can be placed under a positive pressure of inert gas and the plug valve can be fully removed.
This allows direct access to the flask through a narrow glass tube now protected by a curtain of inert gas.
The most common configuration of a solvent pot is a simple round bottom flask attached to a 180° adapter fitted with some form of valve.
The pot can be attached to a manifold and the contents distilled or vacuum transferred to other flasks free of soluble drying agents, water, oxygen or nitrogen.