Joint clip

Polyacetal clips suffer another problem in that the material is strongly affected by the corrosive gases.

[1] Polytetrafluoroethylene (PTFE) joint clips are sometimes used, as its recommended temperature peak matches that of most chemistry work.

The same is true of using Krytox and chemically resistant Molykote (PTFE thickened, fluoro-based) oils and greases for glassware seals.

Some glassware features barbs (Devil's horns / Viking helmet) sticking out the sides of the tapers.

The use of springs is of particular benefit when dealing with positive pressures, as they apply enough force for the glass to operate, but will open the taper if an unexpected excursion occurs.