SMB — Surface Marker Buoy

An SMB is a bright, inflatable tube that you deploy to show your position. Divers use it during safety stops or controlled ascents. It helps boat crews see you through waves or swell. Most divers carry a 1.5 m length for visibility. You might use a DSMB (Delayed SMB) when you need to signal from depth. This gear is vital in places like Komodo because strong currents can pull you far from the boat. I once lost sight of my buddy in Cebu because his buoy failed to inflate properly. Always check your inflator mechanism before you enter the water. A common mistake is trying to deploy it while fighting a heavy surge. Keep your reel organized so you do not tangle your line during an ascent.