On all Elinchrom studio flashes, the set output power is displayed with a number that follows a common scale for all flash models. Elinchrom alone has that function and it facilitates and simplifies the use of studio flashes.
Elinchrom flash units have a common scale for the power setting. This makes it very easy to use aggregates with different strengths and still be able to quickly adjust them so that you get the same amount of light from the different flashes.
If you e.g. uses a unit that has a maximum output of 250 Ws and another with a maximum output of 500 Ws and sets these to 4.0 and they give the same amount of light. The scale is indicated in 1/10 aperture steps and it is very quick and easy to set the right amount of light.When you e.g. measure the light up to aperture 11 but want to use aperture 8, you just lower the unit 1.0 stops. You don't even need to re-measure the light because all Elinchrom studio flashes have very precise and stable regulation of the light amount.