It is herein proposed a novel beacon light device with a circuit board and an enclosure which at least partially encloses the circuit board. The circuit board features a leading board section and a neck board section which is narrower than the leading board section. The enclosure features a wide opening section which has a width equal to or greater than that of the leading board section for permitting passage of the leading board section through the opening. The enclosure also features a narrow opening section which has a width that is smaller than that of the leading board section for preventing passage of the leading board section through the opening.