Mares Rover Octo Normal Use Regulator
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Product Information
The Mares Rover Octo Normal Use Regulator is an octopus (alternate air source) second stage built from Ultralight Technopolymer, fitted with Mares' VAD (Vortex Assisted Design) airflow system and a large one-finger vent button, and finished in high-visibility yellow so a buddy can find it fast. Mares lists this octopus under model number 416557, paired in its manuals with the Rover 15X and Rover R2S first stages.
Who it is for
It suits recreational divers who want a dependable backup second stage for warm to moderate water, and it is equally at home in dive center and rental service: This octopus is described as ideal for intensive rental use, where gear is handled by many divers cycle after cycle. The abrasion resistant technopolymer body and durable rubber vent button are what make that kind of duty realistic.
Key details
- VAD (Vortex Assisted Design): an air bypass tube delivers air to the mouthpiece and creates a swirling vortex with a low-pressure center that holds the diaphragm down during inhalation, for sensitive, easy breathing at all depths.
- Fluid Dynamic Deflector: receives airflow from the bypass tube and directs it to the mouthpiece for smooth delivery.
- Vent button: large, dynamic hinge design, activated with one finger and resistant to free flow in strong currents.
- Body material: Ultralight Technopolymer, abrasion resistant and intended for warm and moderate water temperatures.
- Color: high-visibility yellow, the standard convention for an alternate air source.
Compatibility and sizing
This octopus works with common scuba regulator setups and dive rigs. Mares' manual listings pair model 416557 with the Rover 15X (416254) and Rover R2S (416255) first stages.
DiveCatalog.com is an authorized Mares dealer and a real dive shop in Irvine, California since 2003. Call or chat with us at 888-701-4017 if you want help confirming hose routing or first stage compatibility for your setup.
- Ultralight Technopolymer body abrasion resistant and affordable, ideal for diving in warm and moderate water temperatures.
- VAD, Vortex Assisted Design the air bypass tube delivers air to the mouthpiece, creating a swirling vortex with a low-pressure center that keeps the diaphragm down during inhalation for very sensitive and easy breathing at all depths.
- Fluid Dynamic Deflector receives and properly directs airflow from the bypass tube to the mouthpiece for smooth delivery.
- Durable vent button large button with a dynamic hinge design, easy to activate with one finger and resistant to free flow in strong currents, crafted from durable rubber.
- High-visibility yellow finish so the alternate air source is easy to locate and hand off.
- Built for intensive rental use designed to withstand frequent rental cycles and deliver consistent performance in demanding diving scenarios.
- Pairs with Rover first stages Mares manuals list model 416557 together with the Rover 15X (416254) and Rover R2S (416255) first stages.
- Standard setup compatibility suitable for common scuba regulator configurations and dive rigs.
| Brand | Mares |
| Model | Rover Octopus (Rover Octo Normal Use) |
| Mares model number | 416557 |
| MPN / SKU | 416557NR |
| Product type | Octopus / alternate air source second stage |
| Material | Ultralight technopolymer |
| Airflow system | Vortex Assisted Design (VAD) |
| Airflow management | Fluid Dynamic Deflector |
| Vent button | Large, dynamic hinge design, durable rubber, one-finger activation |
| Color | High-visibility yellow |
| Water temperature use | Warm and moderate water |
| Intended use | Recreational diving and intensive rental service |
| Associated first stages (per Mares manual listing) | Rover 15X (416254), Rover R2S (416255) |
| Barcode | 792460367112 |
⚠️ WARNING: This product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.
Frequently Asked Questions
How often does a scuba regulator need servicing?
Follow the interval in your regulator's manual, since manufacturers commonly specify an annual inspection or a set number of dives and many warranties depend on it. A regulator is life-support equipment, so service belongs with a factory-trained technician rather than being attempted at home. Have it looked at sooner than scheduled if you notice increased breathing effort, free-flow, bubbles, or water in the second stage.
How do I rinse and care for a regulator after diving?
Make sure the dust cap is dry and firmly seated over the first-stage inlet before the regulator goes anywhere near water, because water inside the first stage is the leading cause of internal corrosion. Rinse in fresh water without pressing the purge button, since purging while depressurized can draw water back into the second stage. Shake out the water and hang it to dry with the hoses in wide, gentle loops rather than tight bends.
Can I fly with a scuba regulator?
Regulators travel well and are usually best carried in hand luggage where they will not be crushed or lost. A regulator holds no gas of its own, so there is nothing inherently problematic about it on an aircraft, though the airline and security screeners always have the final say. Pack it dry with the dust cap in place, in a padded regulator bag or wrapped in soft gear.
Can I use my regulator with nitrox?
Many modern regulators are supplied as suitable for nitrox mixes up to 40 percent oxygen, which is the widely used recreational industry standard, while anything above that requires dedicated oxygen-clean equipment and procedures. Confirm what your specific regulator's manual states, and follow your nitrox training and your fill station's requirements. Never assume a regulator is oxygen-service clean simply because it looks clean or is new.
What is the difference between DIN and yoke regulators?
A yoke (A-clamp) fitting clamps over the tank valve and is the most common connection across much of the recreational world, while a DIN fitting screws into the valve and is standard in much of Europe and in technical diving. DIN captures the o-ring inside the threads, which many divers consider more secure, but yoke is often what rental cylinders provide. Adapters exist in both directions, so check what is used where you dive before deciding.
What is the octopus regulator for?
The octopus is your backup second stage, carried so you can share air with a buddy who is out of gas, or breathe from it yourself if your primary fails or free-flows. It is normally on a longer, brightly colored hose so it is easy to find and hand over under stress. Secure it in the triangle between your chin and the bottom of your rib cage so it is instantly accessible and not dragging through sand or coral.
How should I store a regulator between dive trips?
Store it fully dry, out of sunlight, with the dust cap in place and the hoses in wide loops rather than tightly coiled. Avoid hanging it by the second stages for long periods, which stresses the hose fittings; laying it flat in a padded bag or hanging it by the first stage is kinder. If it has sat unused for a long stretch, have it checked before your next trip rather than assuming it is ready to dive.
Which Mares first stages does the Rover Octopus pair with?
Mares' own manual listings pair the Rover Octopus, model 416557, with the Rover 15X first stage (416254) and the Rover R2S first stage (416255). That makes it the matching backup second stage for a Rover based regulator system. It also suits common scuba regulator configurations and dive rigs, so your technician can confirm fitment for other setups.
What does the VAD system do on the Rover Octopus?
VAD stands for Vortex Assisted Design. An air bypass tube delivers air to the mouthpiece and creates a swirling vortex with a low-pressure center, which keeps the diaphragm down during inhalation. The result is very sensitive and easy breathing at all depths. A Fluid Dynamic Deflector receives the airflow from the bypass tube and directs it to the mouthpiece for smooth delivery.
Is the Mares Rover Octopus suitable for cold water diving?
The Ultralight Technopolymer construction is abrasion resistant and ideal for warm and moderate water temperatures rather than cold water work. If you dive cold or ice conditions regularly, speak with us about a regulator system specified for that environment before committing to a backup second stage.
Why does the vent button matter on a backup second stage?
A backup second stage hangs in the water column and can catch flow from currents or boat wash. The Rover Octopus uses a large vent button with a dynamic hinge design made from durable rubber: it is easy to activate venting with one finger, yet resistant to free flow in strong currents. That combination is also why this octopus is presented as ideal for intensive rental use.
Review summary
The Mares Rover Octo is an octopus style alternate air source built from ultralight technopolymer for warm to moderate water. It has a large vent button with a dynamic hinge that can be purged with one finger and helps limit free flow in current, plus Vortex Assisted Design and a Fluid Dynamic Deflector that route air through a bypass tube for smooth inhalation at depth. It comes in high visibility yellow. Written reviews are still few, and early reviewers mention good value. It suits divers wanting a durable backup rated for intensive rental use.
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