First, is a mercury vapor lamp with its box from the 1960's by Sylvania. Second, is a Westinghouse Lifeguard mercury vapor lamp most likely produced in the 1970's or 80's. Last, is a General Electric mercury vapor lamp with its box produced in the 1990's. These types of mercury lamps are used for landscape lighting or as a source of long-wave ultraviolet light using a long-wave UV filter.