This duo is a dual motion sensor and dusk to dawn nightlight allowing you to choose the very best setting for your chosen location. The motion sensor activates the nightlight for about 20 seconds when movement is detected during hours of darkness. The dusk to dawn nightlight is a dimmer light but when movement is detected the light brightens for about 20 seconds and then reverts back to the regular dusk to dawn light. This bright 8 LED torch sits in a charging cradle plugged into the wall and is kept permanently charged by induction charging. If the power fails, or you take the torch from its charging cradle it switches on automatically.