The Marine Inbligent Ultraviolet (UV) Flame Detector, PART no 55000-027MAR, is designed for use where open flaming fires may be expected. It is sensitive to ultra-violet radiation emitted by flames during combustion. Since it requires only UV radiation the Marine UV Flame Detector responds also to stationary flames with no flicker like cigarette lighters and blue gas flames. This product is not compatable with the 45681-321 isolator base