The glass DO probes are available for laboratory fermentation, where sterilization takes place in a separate autoclave. The disposable Van London - Phoenix Co. Dissolved Oxygen Electrodes are compatible with most common oxygen amplifiers. Glass body oxygen electrodes are non-temperature compensated and are required to be kept at a constant temperature. Calibration must be made at the same temperature as the controlled fermentation. The electrodes feature external filling tubes. Electrolyte can be added during use without removing the electrode from the vessel. The electrode membranes can be replaced very easily. However, some skill is involved in replacing them.