List three uses for marker lights.
1. To mark each diver – attach the marker light to your snorkel or cylinder valve.
2. To mark dive boat or surface float – attach the marker light about one metre/three feet up on the flagstaff.
3. To mark ascent/descent line or anchor line – attach several marker lights along the length of the line, with a different color at 5 metres/15 feet to mark the safety stop depth.