What is sidemount or side mounting?

Sidemount or lateral assembly consists of placing bottles on both sides of the body instead of carrying them on the back. But diving in Sidemount is much more than a simple change in the equipment. With the right training, you will find in it a much more rewarding and enriching experience with which you will feel much safer underwater.

Advantages and disadvantages:

Two independent air sources for greater redundancy, which makes a total loss of gas less likely.

Easier access to the valves in case of leaks.

Better trim thanks to the greater ease to move the bottles in the water.

More hydrodynamic position under water.

Availability and flexibility The Sidemount configuration is better for traveling, you can use virtually any type of bottle available.

Transportation of the simplest equipment in those places where access to water is complicated, this can be a great advantage.

More complicated gas management. We must change the regulator during the dive to keep both bottles balanced.

Impossibility to breathe all the gas with a single regulator.

Greater difficulty in carrying deco / stages bottles, requires more practice and dexterity.



he first change that was made with respect to the traditional dorsal mounting took place in the 60s. Thanks to the British speleologist Mike Boon who managed to cross areas impossible to pass in dorsal mounting by moving his bottle to one side and holding it by the taps to a harness Shoulder type.

In the 70s, an interest in side-mounted diving began in North America for reasons not very pleasant, as a less experienced diver without training went through a narrow crack in Royal Springs, Florida, and never managed to get out. Sheck Exley and Wes Skiles, who are 2 of the most experienced speleobuilders in the area, were responsible for the rescue of the diver’s body. After several attempts using the traditional dorsal mount without being able to access the area, Sheck Exley devised a system to place a bottle on the side and thus be able to pass through the crack to the body of the diver and remove it.

It quickly saw the possibilities it offered for the exploration of narrow passages, with which a new wave of explorations in lateral assembly began to expand in the United States. At the beginning of the 80s, they began to create and design harnesses and buoyancy systems that allowed to carry independent bottles. Its objective was to move the bottles to a more advanced position and aligned with the longitudinal and lateral axis of the body. This, supine the beginning of the equipment of sidemouunt or montane lateral “Florida style” or, according to the British, “American side assembly”.

It was not until 1995 when Dive Rite released its TansPac. Soon after, he began selling modified versions of his TransPac, which was the first side-mount system available to the public; system that has evolved to the current Nomad.

At present we can find in the market numerous systems for lateral assembly, which we could divide in two slopes:

Multifunctional systems: they can be used both for lateral mounting and for dorsal, either with mono or with a bibotella. Examples: Hollis SMS 100 or Nomad of Dive Rite.

Exclusive systems for side mounting. Examples: X-Deep, Razor by Steve Bogaerts, Z-System by UTD or Hollis SMS 50.

Curso Sidemount Diver

This course is designed to serve as an introduction to Sidemount diving or both recreational and technical open-water side mounting, and to help divers develop the skills, knowledge and techniques necessary to dive in Sidemount.

Pre requirements:

PADI Advanced Open Water Diver Certificate or equivalent.

Minimum age: 15 years.


The Sidemount Diver course qualifies divers to perform dives using the side mount configuration within the limits established by the highest level of prior certification.


The course of Sidemount Diver consists of a theory session, 1 immersion in confined water and 4 open water dives, normally spread over 3 days.

Some of the exercises that we will practice will be:

1. Put two bottles in the water with minimal assistance.

2. Effectively swimming underwater the following styles:

3. Frog flutter

4. Alternative flutter

5. Demonstrate the proper alternating procedure of regulators, as well as the
ability to read both pressure gauges easily.

6. Share air as a donor and as a receiver (S-drill).

7. Breathe from a regulator by opening and closing the valve simulating continuous flow.

8. Perform the complete valve closing exercise in less than 30 seconds (V-drill).

9. Remove the bottles in the water.

Price: xxx €

Includes: Certification
Specialized equipment: X-Deep harness, 11,1L aluminum bottles, Apex regulators, manometers, bands.

Does not include:
Personal equipment: computer, knife, tablet, etc.