The E series flow indicators are used for flow-rate reading or on gases or on liquids:

- Water treatment plants
- Manufactures (pulp industry, textile industry, etc.)
- Chemical, pharmaceutical industries
- Heating or cooling plants

The E Series are variable area flow indicators, the diver (''float'') moves inside a calibrated conical tube.
These flow indicators may be calibrated accordind the fluid properties and operating conditions.
They accept flow switches, inductive monostable contacts, adjustable over the entire measuring range.