The equipotential plug (8) contains a potential equaliser pin.
The outlet nozzle (6 or 10 for 25 mm. or PG 13.5 version) (standard) and the sampling tap (11, 25 mm. or PG 13.5 version) (optional) allow you to take water samples and empty a module.
The calibration cup (8) can be used to calibrate the pH or redox sensors without dismantling them. It also has a potential equaliser pin.