This demonstration video discusses and shows the features of the Ideations Surface & Underwater Air Horn Dive Alert Plus V.2. The surface and underwater signaling device can be used for in or above the water. On the surface a blast of sound that can be heard up to a mile away. The Dive Alert is great for getting your buddy´s attention underwater. The signaling device attaches between the power inflator and the low pressure hose. Installation is easy and takes only a moment. The Dive Alert is a specially designed, small, lightweight air horn which uses a small amount of air from your scuba tank to make a piercingly loud sound.