Lift Bags - Marking Tubes

The Surface Marking Tube (SMT) is also known as Surface Marker Buoy (SMB) or Delayed SMB (DSMB)

For an overview of all features and specifications see the table details in our TekTip below.

19 Items

per page
Set Descending Direction
Tek Tip Warning Image WARNING

Some of the lift bags and surface marking tubes include a non-locking inflation connection fitting that supports easy and rapid power-inflation at the surface using the standard quick-disconnect low-pressure BC inflator hose. However, there are some safety concerns using that mode for deployment while at depth. Disconnecting the inflator hose from your BC at depth could compromise your buoyancy control in an emergency. Although the inflation connector on the device is non-locking, there is a possibility connectors could jam and fail to easily separate if the connectors are not clean and well maintained. As with any such device, it is also possible to create enough lift such that it could begin to drag you to the surface if there is any delay in release and the rapid power-inflation feature can reduce the time available before release.

For deployment at depth we suggest using an alternate low-pressure quick-disconnect inflator hose mounted on a stage or bailout bottle, rather than the primary BC inflator hose, for power inflation of this device. If this is your first experience with power-inflation lift bag or marking tube deployment at depth, first practice this type of deployment under controlled conditions.

How to Choose Between Lift Bags and Marking Tubes

Surface Marking Tube vs Lift Bag Divers are sometimes confused about the difference between lift bags and surface marking tubes. Our factual but easy-to-read article helps you choose the appropriate bag by giving you information on:

  • Why is one better at carrying a load to the surface
  • Why is one a better surface marker
  • Which has a dump valve that can be regulated on ascent
  • Which has an over pressure relief valve (OPV) that cannot be regulated on ascent

Click Here to read Lift Bags versus Marking Tubes.

Lift Bags and Surface Marking Tube Features

Device Size
Power Inflate
Color Additional
OMS Small Lift Bag {50 lb | 23 kg} Semi-Closed No Orange Compact Size, Top Handle
Dive Rite Lift Bag {75 lb | 34 kg} Open No Orange Top Handle, Reflective Tape, Built-in Sleeve, D-rings
Mares XR Lift Bag {80 lb | 36 kg} Closed Yes Orange D-rings Top & Bottom, Sewn-in Bungee Loop
OMS Large Lift Bag {125 lb | 56 kg} Semi-Closed No Orange High Capacity, Top Handle
DGX Safety Sausage {44 in | 112 cm} Closed Oral Only Orange or Yellow SURFACE DEPLOY ONLY
Mares XR Small SMT {39 in | 100 cm} Closed Yes Orange Compact, Sewn-In Bungee loop
Dive Alert Small SMT {46 in | 117 cm} Closed Yes Orange Built-In Pocket, Reflective Tape
Dive Alert SMT {5.4 ft | 1.7 m} Semi-Closed No Orange Reflective Tape
Dive Alert Deluxe SMT {5.4 ft | 1.7 m} Hybrid Yes Dual Color Built-in Pocket, Reflective Tape
Mares XR SMT {5.9 ft | 1.8 m} Closed Yes Orange or Yellow SOLAS Tape, Clear Pouch
OMS SMT {5 ft | 1.5 m} Semi-Closed No Yellow Wide {8 in | 20 cm}
OMS Slim SMT {6 ft | 1.8 m} Hybrid Yes Orange Weighted, Reflective Tape, Clear Pouch
Dive Rite SMT {5 ft | 1.5 m} Hybrid Yes Orange Built-in Sleeve, Reflective Tape, Wide {8 in | 20.3 cm}
Highland Giant SMT {10 ft | 3.1 m} Hybrid Yes Orange HUGE {22 in | 56 cm} Circumference, SOLAS tape
  • Open = The bottom of the bag or tube is completely open and unrestricted. To fill with gas hold the opening over a second stage regulator or BC oral/power inflator, or hold the mouthpiece inside the opening, and operate the device to release gas out the mouthpiece into the bag or tube.
  • Semi-Closed = The bottom of the bag or tube is open and inflates the same way, although more slowly, plus incorporates an funnel-shaped internal restriction (aka "duck-bill") that limits gas from escaping once it enters.
  • Closed = The bag or tube is completely sealed and uses a one-way valve nipple for oral inflation. Most inflation nipples also have a non-locking fitting that supports easy and rapid power-inflation by pushing on (and holding in place) a standard quick-disconnect low-pressure BC inflator hose.
  • Hybrid = The bag or tube is both semi-closed and also includes an inflation nipple. Hybrid designs support the choice of any of the three methods of inflation: from the bottom opening, oral inflation, and power-inflation with a BC low-pressure hose.

Message Icon