What uses the combination of colors red and black to indicate isolated dangers?

The isolated danger buoy is specifically designed to indicate isolated dangers in navigable waters, such as underwater rocks or wrecks, that are not immediately visible. The use of red and black colors on this buoy is standardized to provide clear and recognizable signals for mariners. The red typically represents the upper part of the buoy, while the black shows the lower portion.

This color combination serves an important purpose in maritime navigation, as it effectively communicates to boat operators that they should avoid the area surrounding the buoy. The isolated danger buoy also features two horizontal black bands, which help in distinguishing it from other buoy types. This clarity is essential for safety, ensuring that navigators can quickly identify the potential hazard without confusion over other navigational markers.