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SMBs

Quality delayed surface marker buoys (DSMBs), surface marker buoys (SMBs), dive/cave/wreck reels, dive finger/jump spools and lift bags from The Scuba Doctor Dive Shop are essential safety equipment for scuba diving.

If you need help deciding which dive reel, wreck reel, cave reel, or finger/jump spool is right for you, or want some top tips for using reels underwater, please read our Dive Reel Buying Guide.

Most divers refer to DSMBs as SMBs, which is why the category here is called Surface Marker Buoys (SMBs). But technically they're different devices and the items in this category are actually DSMBs. See Surface Markers for our range of SMBs.

A Delayed Surface Marker Buoy (DSMB) is deployed whilst the diver is submerged and generally only towards the end of the dive. A reel or finger spool and line connect the buoy on the surface to the diver beneath the surface.

DSMBs are not intended to be used to lift heavy weights. That's what a Lift Bag is for.

Tech Tip: Basic Care and Maintenance for Your Reels and Spools

Most overhead cavern and cave divers require three reels: one large "primary" reel with at least 120 metres (400 ft) of line, plus two smaller "safety" reels with about 45 metres (140 ft) of line. Many divers also carry one or more 15 metre (50 ft) or longer compact finger spools for gap jumps. Depending on the mission and instructor, sometimes a finger spool can be substituted for one of the required safety reels.

Open water technical classes require a 45 metre (140 ft) or larger reel and large surface marking bag. Depending on local conditions many instructors also require a backup bag and reel. Sometimes a finger spool is substituted for the reel.

As with most dive equipment, you should rinse your reel with fresh water following each dive. You should also periodically disassemble the reel, and remove any build-up of salt or sediment on its internal parts. We recommend pulling some or all of the line off the spool before each dive, then rewinding it neatly but not too tightly, so as to prevent the possibility of jamming during line deployment. If the line on your reel is new or very dry, we recommend pulling the line off into a bucket of water. This will moisten the line, precluding it from swelling on the reel and further preventing the possibility of jamming or damaging the spool.

Overloaded reels and spools are common and too much line can cause jams during initial deployment. If you are having a problem with jams, check the length of the line and try removing some excess if your reel or finger spool has been overloaded. Many finger spools come loaded with too much line, often so bad that they can't be used properly until some line is removed.