Halcyon DAM stands for Diver Alert Marker, a type of surface marker buoy (SMB) used to ensure the safety of scuba divers. It's a brightly colored inflatable buoy deployed from underwater to signal a diver's location to boat operators and surface support teams. It can be inflated by mouth or with a low-pressure inflator hose and often features an overpressure relief valve, making it essential safety equipment. * 1m, 6lb (2.7kg) * Inflates from a mid-pressure BC hose (with no-lock function) * Equipped with an overpressure valve Defender Pro 1 Safety Spool * Spool, 30m line length * Double-ended snap included I've stopped diving, so I no longer need these.