Halcyon Symbios Rebreather

Rebreather

Symbios™ Chest Mount Rebreather

Rebreather

Symbios™ Chest Mount Rebreather

The Halcyon Symbios™ is a next-generation chest-mounted closed-circuit rebreather (CCR) designed to integrate seamlessly into the way divers explore.

Compact, streamlined, and engineered for unmatched work-of-breathing in all positions, Symbios™ empowers divers to go further, stay longer, and experience the underwater world with new clarity.

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Engineered for Exploration

The Halcyon Symbios™ Rebreather combines innovation, safety, and streamlined design. With redundant wireless communication, hybrid O₂ sensing, and a patented BOV/ADV system, it delivers excellent breathing performance and intuitive alerts. Its modular, travel-friendly build is compact yet powerful, offering easy trim, large CO₂ capacity, and seamless connectivity across the Symbios ecosystem for exploration without limits.

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Symbios CM Rebreather

Specifications

Key Highlights

Sleek, ultra-slim design that’s lightweight and unobtrusive
Transflective color display for excellent readability in all light conditions
Responsive tactile buttons for confident use underwater
Rechargeable battery (~40 hours runtime) for extended dive trips
Clean, easy-to-read interface with customizable layouts
Numerous customizable parameters to suit diver preference
Constant evolution with regular firmware upgrades
Powerful Symbios App integration, extending features and logs
Scales with a diver’s needs, from recreational to expeditionary use

Built for Modern Divers

Streamlined Performance: A low-profile chest design that improves trim, comfort, and accessibility.
Advanced Safety: Dual sensing (electrochemical + GreenFlash™ digital O₂), tactile vibration alarms at the chest, and bold visual alerts for critical conditions.
Smart Technology: Adaptive setpoint control, Symbios App pairing for pre-dive checklists, firmware updates, and dive log review.
Exploration Ready: Designed for both recreational and advanced technical dives, fully EN 14143 compliant.

Handset & HUD Integration

Pair the Symbios™ Rebreather with the Handset or HUD for a fully connected experience. Both are part of the unique Symbios ecosystem, delivering intuitive control and critical dive data at a glance.

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California Residents Only

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SCRUBBER

Scrubber type - specify all that apply: Axial
Scrubber volume (Kg): 2.7kg
Temperature stick (scrubber monitoring): No
Scrubber duration CE: CO2 1.6l/m 5mb bypass — TBC

LOOP

Work Of Breathing (WOB): CE 100m test, trimix, horizontal — TBC
Work of Breathing (WOB): CE 40m test, Air, vertical — 1.6 joules/Litre
Active loop volume (liter): CE Test
Counterlung volume (liters) - options?
Backmounted Counterlung: No
Frontmounted Counterlungs: Yes
Detachable counterlungs (w/o unit disassembly): Yes
Oxygen injection side: Before Scrubber
Loop direction: Right to left
Automatic Diluent Valve: Yes
Diluent Shut-off Valve: No
Bail Out valve (BOV): Yes (Built into the ADV system)
Mouthpiece Retaining Strap: Yes
Flood Resistant - specify: Exhalation Lung has purgable water trap.
All electronics sealed from water ingress

HEAD & SENSORS

Plug and Play Head Components - user replaceable? No
User Upgradeable Firmware: Yes
Number of O2 cells - options(?) 3 (2 × Analogue + 1 × Solid state or 3 × Analogue)
Number of solenoids: 1
Means of O2 addition (solenoid only, leaky valve, hybrid): Solenoid + MAV
Solid state O2 sensor: Yes, Greenflash
Independent secondary O2 reading:
Oxygen cell tester (>1bar). Specify built-in or add-on (pot): No
Helium sensors: No
Gaseous CO2 sensors: No
Dual Computers: Yes
Independent electronics (specify): 2 monitoring systems in the head, each with independent transmitters
CCR Bail-Out mode: No
Battery type: Rechargeable
Battery life dive time (hours):