The appliance operates similarly to the existing socket until it detects that the power has been removed, then automatically switches to battery operation and illuminates the bright light emitting diodes.
The rechargeable battery enables the light emitting diodes to stay on independently for up to a minimum of three hours or until the electrical power returns.

The idea was brought about after seeing the 24-storey Grenfell Tower fire which broke out on 14 June 2017.
When a fire occurs the electrical supply normally fails and if emergency light power sockets were installed, then you would have illumination close to the floor in a smoke filled area.