An interchangeable power source light device has an AC power sealed-unit that fits into a uniform compartment of the light device housing. The AC power sealed-unit can be replaced by a DC power battery-pack, which also fits into the uniform compartment-means of the light device housing. The light device may have a built-in light source within the housing for connection with the sealed-unit or battery unit by to deliver electric signals from the sealed-unit or battery pack to the light source. Each sealed-unit and battery pack not only has its own power source, but also circuitry and a trigger, and optionally other light source(s) having low power consumption such as an LED(s), electro-luminescent (EL) element, organic LED, or organic EL element.