The REDi-lite Day/Night kit was created so your REDi-lite light can be more than just a skylight during the day. The Day/Night kit allows you to choose between two power sources, Solar and the Grid.
This is manually done by simply flicking a switch. By having the switch mech in the Day position allows the light to be powered by the sun, if the switch is in the Night position than your light will be powered by the transformer. An additional on/off switch is provided for full control.