The S7 CCR is a compact mechanical closed-circuit rebreather (mCCR) designed for technical, cave, sidemount, bailout, exploration, and other specialized diving applications.
Its key design focus is an extremely compact and lightweight form factor, with the unit weighing approximately 5 kg.

CCR stands for Closed-Circuit Rebreather.
Unlike an open-circuit scuba system, a CCR recirculates the diver’s exhaled gas. Carbon dioxide is removed by the scrubber, while oxygen is added to maintain the required oxygen partial pressure.

The S7 is a manual closed-circuit rebreather (mCCR).
Oxygen and diluent are manually added to the breathing loop through the Dual MAV (Manual Addition Valve) rather than being automatically injected by a solenoid.

The S7 weighs approximately 5 kg.
The final weight of a complete diving configuration will depend on the cylinders, gases, computer, mounting system, and other equipment used.

The manufacturer describes the S7 as approximately:
The height of a 2-litre cylinder
The diameter of a 3-litre cylinder
Approximately 5 kg in weight
Its compact size makes it particularly suitable for travel and confined-environment diving.

Yes.
The S7 was designed with portability in mind. Its compact dimensions allow the unit to fit into approximately half of a small suitcase.
Airline and transportation regulations still apply to cylinders, oxygen, sorbent, and other diving equipment.

The basic breathing cycle is:
Exhalation → Counterlung → Scrubber → CO₂ removal → Oxygen management → DSV → Inhalation
The breathing gas is continuously recirculated through the closed loop.
Oxygen and diluent can be manually added through the MAV system.

The scrubber is the component responsible for removing carbon dioxide from the diver’s exhaled gas.
The S7 uses an axial scrubber design.

The S7 scrubber has a capacity of approximately 1.9 kg of sorbent.

The manufacturer states a duration of up to approximately 4 hours, depending on diving conditions.
Actual scrubber duration depends on factors such as:
Water temperature
Diver workload
Breathing rate
Sorbent type and condition
Dive profile
Other environmental conditions
The stated four-hour duration should therefore not be treated as a universal operating limit.

Yes.
For certain cave and expedition applications, approximately 1 kg of sorbent can be used, with the manufacturer indicating up to approximately 2 hours under appropriate conditions.

The manufacturer states that filling the axial scrubber takes approximately 2 minutes.

Yes.
For water temperatures below approximately 6°C, the manufacturer recommends using a neoprene cover to help maintain scrubber efficiency.
The compact breathing loop also reduces the distance over which the breathing gas is exposed to cold water.

The counterlung is an essential part of the closed breathing loop.
It accommodates changes in gas volume during breathing and depth changes and helps maintain the appropriate breathing volume within the loop.

The S7 counterlung has a volume of approximately 5.4 litres.

Yes.
The counterlung incorporates approximately 1 litre of water-trap capacity.
This helps prevent water from reaching the scrubber.

The S7 counterlung incorporates an OPV for rapid water removal.
A dump valve is also provided for removing excess gas from the loop.

MAV stands for Manual Addition Valve.
The S7 uses a Dual MAV system for manually adding oxygen and diluent to the breathing loop.

The oxygen MAV is used to manually add oxygen to the breathing loop and maintain the required oxygen partial pressure.

The diluent MAV can be used to:
Adjust loop oxygen partial pressure
Maintain loop volume
Compensate for gas compression at depth
Perform diluent flushes
Support appropriate emergency procedures

The manufacturer specifies an oxygen orifice flow rate of approximately 1 litre of O₂ per minute.
The system also incorporates a needle valve with adjustable resistance.

The standard configuration includes:
An inflator-style connector for diluent
A 9/16-inch male connector for oxygen

Yes.
The S7 can be connected to external gas sources.
For serious diving applications, the manufacturer recommends Swagelok QC4 for oxygen and QC6 for diluent.
Using different connector sizes helps reduce the risk of accidentally connecting the wrong gas.

The S7 is designed for three oxygen cells.
The manufacturer specifies compatibility with R22SMB-type cells using the appropriate coaxial connection.

The manufacturer indicates compatibility with both galvanic and solid-state cells, provided they have the appropriate coaxial connector and are compatible with the monitoring system being used.

The oxygen cells measure the oxygen concentration in the breathing loop.
The resulting partial pressure of oxygen (PPO₂) is displayed through a compatible monitoring system or dive computer.

The S7 supports several monitoring configurations, including:
Halcyon transmitter integrated into the S7 head, with a Halcyon computer and HUD
Single AK4 cable for a Shearwater computer
AK4 + Halcyon transmitter for simultaneous Shearwater and Halcyon integration
Two AK4 cables for a Shearwater computer and Shearwater NERD

No.
The listed Ready to Dive Unit does not include a computer.

DSV stands for Dive/Surface Valve.
It allows the diver to breathe from the closed loop while providing a means of isolating the breathing loop from the surrounding water.

The S7 uses a compact DSV specifically designed for the system.
The manufacturer highlights its small size and low weight as part of the overall compact design philosophy of the S7.

Yes.
Sidemount is one of the key applications of the S7.
The unit can be mounted alongside the diver in a stage-like configuration.
The compact design can provide advantages in confined environments and cave diving.

Yes.
The S7 can be configured alongside:
A single cylinder
A twinset
The manufacturer also describes configurations using a 1- or 2-litre oxygen cylinder mounted on the unit.

Yes.
The manufacturer shows a recreational-style configuration consisting of:
Single cylinder + S7 + 1-litre O₂ cylinder

Yes.
A configuration consisting of:
Twinset + S7 + 2-litre O₂ cylinder
is also supported.

Yes.
The S7 can be configured as a bailout CCR for appropriate technical diving applications.

Yes.
The manufacturer describes a Dual CCR configuration using two S7 units.

Yes.
Cave diving is one of the primary applications for which the S7’s compact design is intended.
Its small dimensions can be particularly advantageous when navigating restricted passages.

Yes.
Sump diving is specifically listed among the intended applications of the S7.

The manufacturer lists the S7 for serious deep diving applications.
However, the official website does not specify a single maximum operating depth.
Actual depth limits depend on the configuration, gases, PPO₂ limits, training, bailout strategy, and applicable manufacturer procedures.

If you already hold a valid S7 CCR course certificate, you can order your S7 rebreather directly through the S7 configurator.

If you do not yet have an S7 CCR certification, you must first select an authorized S7 instructor. Your S7 CCR course and rebreather order will then be arranged through your selected instructor. (s7ccr)

Yes.

Direct ordering through the S7 configurator is available to divers who already hold a valid S7 CCR course certificate.

If you do not have the certification yet, the order must be arranged through an authorized instructor together with your S7 CCR training. (s7ccr)

No.

All prices displayed in the S7 configurator are exclusive of VAT. (s7ccr)

Yes.

The S7 configurator allows customers to select additional components according to their intended configuration, including counterlungs, MAV systems, oxygen cells, gas connectors, monitoring equipment, and the Cave Shield. 

If you do not yet hold an S7 CCR certification, select an authorized instructor from the S7 instructor list.

The instructor will arrange both your S7 CCR course and rebreather order.

Use the official S7 Instructor list to find an authorized instructor and begin your S7 CCR training and purchase process. 

You can pay into one of our companies' accounts. You can choose to order from either our EU company or our Kazakhstan company.

It depends on how you pay for your order.Payments from companies● For companies outside Portugal and Kazakhstan, VAT is 0%.● For companies registered in Portugal, VAT is 23%.● For companies registered in Kazakhstan, VAT is 16%.Payments from individuals● For EU residents, Portuguese VAT is 23%.● For Kazakhstan residents, VAT is 16%.● For residents of other countries, we issue an invoice with 16%/23% VAT, but we refund the VAT if you provide export documents (see “How to refund VAT?” below).

You can follow these steps:1. Provide us with your home address and ID/passport number — the same details you will use at border control.2. We issue an invoice with this information.3. You declare the goods at border control and obtain export documents.4. You send us these documents, and we verify them with our accountant and the Tax Office.5. If everything is in order (which is usually the case), we refund the VAT.
Hint: We suggest using a broker to help you go through the export procedures smoothly, but it's up to you.

There are many options. For example, an inflator connector (for Diluent) and a 3/8" male – 9/16" male adapter (for Oxygen), but we recommend using Swagelok QCs for the best experience and safety.

Yes.
The S7 is a manual CCR and requires appropriate CCR training and familiarity with the specific equipment configuration.

A person can purchase equipment, but purchasing a CCR is not a substitute for CCR training.
The S7 is designed primarily for specialized diving applications and should be used only within the diver’s training, experience, equipment configuration, and established procedures.

The official S7 website maintains a list of approved instructors and representatives by region.
Prospective customers should contact an instructor to discuss training, configuration, availability, and purchasing options.

No.
The S7 is a manual CCR.
The diver manually manages oxygen addition through the MAV system while monitoring PPO₂.

The S7 is designed to be used with an appropriate PPO₂ monitoring system.
The manufacturer provides multiple computer and monitoring configurations for this purpose.
Operating a CCR without appropriate monitoring should not be considered a normal or safe operating procedure.

No.
The oxygen cells must be compatible with the S7’s connection system and the selected monitoring equipment.
The manufacturer specifies three-cell configurations and lists compatible cell types.

The S7 should not be treated as a beginner’s diving system.
It is an mCCR intended for technical and specialized applications, including cave, sump, deep, sidemount, bailout, and exploration diving.
Appropriate CCR training and experience are essential.