It is an electric, tankless unit designed to heat water as it flows through the device, typically used in bathrooms for showers.
Temperature Control (Bottom Knob): This allows you to adjust how hot the water gets.
Pump Control (Top Knob): This specific model (EP) includes a built-in booster pump, which is useful if your home has low water pressure.
ELSD (Earth Leakage Sensing Device): This is a critical safety feature. The "Test" and "Reset" buttons are used to ensure the internal circuit breaker is working to protect you from electric shocks.
Pump Activator: A button to manually toggle the booster pump on or off.