The Customs Museum currently has a collection of Customs warning bells and fog cannons, which were mostly installed on lighthouses and lightships to warn ships, identify directions, and indicate positions.

Being 500 kg in weight, 80 cm in diameter and 85 cm in height, this bell was originally installed on a ship. The bell chimes when it is foggy to issue a safety warning for ships passing nearby waters.

Upon hearing vessels passing nearby waters when it is foggy, the staff of a lighthouse would fire the fog cannon as a signal of safety warning.