The silhouette of a freediver in the water is barely visible. Using a buoy makes you noticeable, and boat operators and water sports enthusiasts will keep their distance. A line is attached to the diving buoy, with a bottom weight at its end. When the line is taut, it serves as a visual reference for vertical descent and ascent and allows you to stop the descent immediately in case of problems. This is especially important to prevent damage to your eardrums (barotrauma) in case of difficulty equalizing pressure.

A buoy typically offers attachment points for additional equipment, such as a dive knife, a depth gauge (sonar), a signal whistle, and similar items. When diving in summer or at sea, carrying a water bottle in the buoy is also advisable. Spearfishers often attach extra spears to the buoy to access a shorter or longer spear depending on the situation.”