Box light
A compartment light is a flashlight that its voltage from a 4.5 V - flat battery relates. It was mostly used in the 20th century. Box lights have a compact and functional design due to the flat battery with high energy density (5900 mAh). They usually have an angular metal housing into which the battery is inserted by opening the back cover. A continuously adjustable light cone is usually mounted on the housing.
Box lights often have a Morse code button for flashing signals and a filter slide with which a red or green filter can be pushed in front of the light bulb . The luminaire is therefore especially suitable for maritime applications. Due to the decreasing market presence of flat batteries and alternative mobile light sources, box lights have lost a lot of their importance.