Pro EQ allows for manual fine tuning of your hearing profile via the Nura app after you've created a personalised hearing profile. Simply press the Pro EQ icon and adjust the 5 sliders:
You can adjust the following bands: 400Hz, 1kHz, 2.2kHz, 5kHz, 10kHz. To snap the sliders to 0 simply tap the "reset" button. Turn the ProEQ on and off with the toggle switch.