https://skippersreview.com/review/new/ideations-design-seattle
DiveAlertPLUS uses a small amount of air from your SCUBA tank to make a piercingly loud sound in air or water. People have been able to hear a DiveAlertPLUS one mile away from a diver in need above water. In conditions where visibility is limited, a DiveAlertPLUS can be a life saver. Underwater you can sound for attention quickly with a squeeze of the device.