Stirrer guides are of different types.

With fused-on stirrer bearing.

GTS-vacuum-stirrer, with PTFE-insert and interchangeable PTFE-vacuum-seal, screw cap GL 25.

With PP-insert, 8 mm Ø and screw cap GL 25, made of melamine.

With cooling jacket and PTFE-insert, with interchangeable PTFE-vacuum seal and screw cap GL 25, made of melamine.