Which Second Stage Regulator Is Best for a Full Face Diving Mask?

Our Pick and How the List Was Built

A reliable regulator ensures that every breath remains effortless, preventing the buildup of CO2 that occurs when breathing resistance becomes too high. Consistent airflow is the primary goal for anyone using a full face diving mask.

The Rego LV4403B66R Low Pressure Second Stage Regulator delivers this consistent flow to keep your breathing smooth. For a slightly lower price point, the Rego LV4403B4 works well, and the Rego LV4403B46R provides a specialized 90 Degree Backmount Design for different configurations.

Our team evaluated 16 Second Stage Regulators and chose 10 to compare here at Scuba Forge. These options cover a price range from $105.8 to $145.

See the article scope to understand which specific models and categories are included in this guide.

Check the minimum requirements to ensure your equipment meets the necessary safety standards for full face masks.

Browse our top picks for a quick glance at the best-performing regulators currently available.

Second Stage Regulators for Full Face Diving Mask Compared Side by Side

Prices are approximate and move frequently – check the current price before deciding.

The Rego LV4403B66R Low Pressure Second Stage Regulator fits this topic best because it provides a 10 PSI pressure rating for full face mask use.

Each Pick for Full Face Diving Mask, Examined One by One

The 3 picks below are reviewed in the same order as the cards above.

Rego LV4403B66R Low Pressure Second Stage Regulator

The Rego LV4403B66R is a low-pressure model designed to provide the consistent airflow required for full face diving mask setups. It is specifically identified as a low-pressure regulator, which is the industry standard for these masks to ensure steady breathing.

What we like: This regulator features a 3/4″ Female NPT Inlet and Outlet, which provides a specific connection point for your breathing apparatus. It is rated for a 10 PSI pressure, a measurement of the maximum force the device can withstand. The 5-pound weight is a decisive figure for those monitoring the mass of their underwater gear.

Keep in mind: The 3/4″ x 3/4″ hose diameter is a specific size that you must verify against your mask’s requirements before ordering. This model does not state a purge button, which is a component used for clearing water from the mouthpiece.

Rego LV4403B4 Low Pressure Second Stage Regulator

You can choose the Rego LV4403B4 if you need a low-pressure regulator that meets the standard requirements for mask-compatible scuba gear. This model is a low-pressure unit, ensuring the airflow remains consistent during your dive.

What we like: This model features a straight through design and a 10 PSI pressure rating. It holds a 5.0 rating from buyers who have used it for their breathing apparatus. The 1/2″ x 1/2″ hose diameter provides a standard connection for many mask systems.

Keep in mind: While it provides a 10 PSI pressure rating, the data does not state if this unit includes a purge button to clear the mouthpiece. The 1/2″ hose diameter may not match systems requiring the larger 3/4″ fitting.

Rego LV4403B46R Low Pressure Second Stage Regulator

The Rego LV4403B46R is a low-pressure regulator that provides a specific 90-degree backmount design for your full face mask. It meets the low-pressure requirements necessary for safe and consistent airflow in mask environments.

What we like: This regulator offers a 90-degree backmount design and a 10 PSI pressure rating. It has a 1/2″ x 3/4″ hose diameter, providing a unique connection point for specific mask configurations. It also holds a 5.0 rating from buyers.

Keep in mind: The data for this model does not state a purge button, which is used to clear water from the mouthpiece. You should confirm the “fits specific model” note by checking your own equipment’s requirements.

Which regulator is the most reliable for heavy breathing under high demand?

Reliability for heavy breathing is determined by the low-pressure design, which is the standard for full face masks to ensure consistent airflow. All three models listed here are low-pressure regulators with a 10 PSI pressure rating, which measures the maximum force the device can withstand. None of these picks state a figure at the high-performance level of the Apeks XTX or Scubapro S620 Ti, which are the high-end engineering benchmarks for flow. Because the data does not state a specific flow rate or breathing resistance value, you should rely on the low-pressure designation to ensure consistent delivery during your dive.

Consult the buying guide to learn the key criteria you should consider before making a purchase.

You can also view our full spec breakdown of the G260 for more technical details.

How to Choose a Second Stage Regulator for Full Face Diving Mask

Why a low pressure delivery system ensures consistent airflow for full face masks

Prioritize a low-pressure delivery system to ensure consistent airflow and prevent the gas-out that occurs when a regulator cannot meet the volume requirements of a full-face mask. These systems deliver air at reduced pressures, which is the industry standard for full-face masks to ensure safe and consistent airflow. The Rego LV4403B66R, Rego LV4403B4, and Rego LV4403B46R all provide a 10 PSI pressure rating. This specific pressure level is what allows for a steady supply without the high-pressure spikes found in standard configurations. How much pressure does your specific mask require? The 10 PSI rating on these three models provides the standard low-pressure output used for most full-face mask setups. While high-end benchmarks like the Apeks XTX or Scubapro S620 Ti are known for high-flow engineering, these low-pressure models focus on the specific needs of mask-integrated breathing.

How moisture resistance prevents internal condensation from seizing the regulator mechanism

Check for moisture resistance to prevent internal condensation from causing the mechanism to seize or become difficult to operate. Internal moisture accumulation is a common failure mode where water droplets build up inside the housing. While the specific moisture protection ratings for these models are not stated, the 11″ water column across all three Rego models indicates the depth of water they can withstand before being submerged. This measurement tells you the depth limit for the device’s operation, not the internal seals’ durability. For long-term reliability, you should ensure your first stage compatibility allows for a clean, dry connection to the second stage to minimize water entry points.

Compact Profile for Mask Mounting

Select a compact profile to ensure the regulator does not interfere with the mask’s seal or the diver’s visibility. The Rego LV4403B66R features a back mount design, which helps position the unit away from the face. The Rego LV4403B46R offers a 90-degree backmount design to further streamline the profile against the head. Because these units are used on the “structure,” their mounting orientation determines how much they protrude from the mask. You should measure your mask’s mounting clearance and compare it against the 90-degree orientation of the LV4403B46R or the straight-through design of the LV4403B4 to see which fits your specific mask’s geometry.

Ease of Breathing Under Load

Evaluate breathing resistance to ensure the work of breathing remains low as you change depth, which prevents CO2 buildup and exhaustion. A balanced first/second stage design determines if the breathing resistance changes as the diver changes depth. While the data does not state a specific resistance value for these models, the 10 PSI pressure rating is the primary factor in maintaining a consistent flow. The Rego LV4403B46R and Rego LV4403B4 both feature a 1/2″ x 3/4″ or 1/2″ x 1/2″ hose diameter, which impacts how much air moves through the tubing. For a full-face mask, the 11″ water column rating across these models defines the operational environment where these flow characteristics remain consistent.

View the comparison table to see the technical specifications of each product side by side.

Use the audience checklist to identify which specific model best suits your personal diving needs.

What Each Job Calls For vs What These Picks State

Match the job you actually need done to the figure it calls for, then check which picks state that figure or more. Where none do, the row says so.

These figures are the levels this category is generally held to, not manufacturer claims. A pick at or above a figure states that number; how it reaches it and the rest of your setup still decide the job, so check them against your own workload before buying.

Who Buys Second Stage Regulators, and What It Really Costs

Review the setup and warranty notes for information on installation requirements and manufacturer support.

Explore the detailed reviews for an in-depth look at the performance and features of every model.

Visit the FAQ to find quick answers to common questions about second stage compatibility.

Getting Started with Any of These Picks

Pre-purchase requirements for full face mask regulators

You must have a compatible high-pressure cylinder or pony bottle to provide the air supply for these second stage regulators.

• The Rego LV4403B66R Low Pressure Second Stage Regulator requires a 3/4″ x 3/4″ hose diameter to connect to your system.
• The Rego LV4403B4 Low Pressure Second Stage Regulator uses a 1/2″ x 1/2″ hose diameter.
• The Rego LV4403B46R Low Pressure Second Stage Regulator connects via a 1/2″ x 3/4″ hose diameter.

Verifying your regulator upon arrival

Warranty coverage and return policies vary by seller and country.

• Check the 11″ water column measurement on all three models to ensure the breathing resistance meets your requirements for consistent airflow.
• Verify the pressure rating of 10 PSI on the Rego LV4403B66R, Rego LV4403B4, and Rego LV4403B46R to confirm they are configured for low-pressure mask use.
• Inspect the 90 Degree Backmount Design on the Rego LV4403B46R to ensure the exhaust port orientation matches your specific mask mounting hardware.
• Confirm the hose diameters match your existing setup, as the 3/4″ and 1/2″ fittings are not interchangeable without adapters.

Perform a dry-run pressure test with your cylinder to check for leaks before your first underwater use.

Compatibility with existing tanks and pony bottles

These regulators will work with your current pony bottle or primary tank if the connection points match the specified hose diameters.

The Rego LV4403B66R Low Pressure Second Stage Regulator uses a 3/4″ Female NPT Inlet, while the Rego LV4403B4 and Rego LV4403B46R use 1/2″ connections. You must ensure your tank’s output matches these specific sizes. Because these are 10 PSI low-pressure units, they are designed to deliver the lower pressures required by full face masks rather than the high pressures of standard scuba gear.

What Buyers Still Want to Know About Second Stage Regulators for Full Face Diving Mask

Is it worth spending more on a high-end regulator for a full face mask?

Spending more on a high-end regulator for a full face mask provides a higher engineering benchmark for reliability and flow, similar to how a high-end engine provides smoother power delivery than a base model. While the Rego LV4403B66R costs $145, the Rego LV4403B4 is available for around $105.80, providing a lower-cost entry point that still maintains a 10 PSI pressure rating for consistent airflow.

What happens if the regulator freezes or gets clogged with salt?

A regulator that freezes or gets clogged with salt can lead to moisture accumulation or a free-flow, where the device fails to close and exhausts the air supply rapidly. These low-pressure regulators, including the Rego LV4403B46R, use a 10 PSI pressure rating to ensure steady delivery, but internal moisture can cause the mechanism to seize if not maintained.

Which second stage regulator is best for a budget-friendly entry point?

The second stage regulator for a budget-friendly entry point is the Rego LV4403B4, which is priced at around $105.80. This model provides the 10 PSI pressure rating required for full face masks while offering a straight-through design for simplified airflow.

How do I choose a regulator for a full face diving mask?

Choosing a regulator for a full face diving mask requires identifying a low-pressure model to ensure safe and consistent airflow. You should select a model with a 10 PSI pressure rating, such as the Rego LV4403B66R, which also features a 3/4″ x 3/4″ hose diameter for specific connections.

Consider looking into second stage regulator alternatives for different results if these models don’t fit your needs.

Who Should Skip These Second Stage Regulators

For those prioritizing weight, the Rego LV4403B66R weighs 5 pounds. The other two models do not state a weight in the data. Because weight is the measure of the unit’s heaviness, you should consider how much mass you are willing to carry on your mask setup before choosing between these models.

If you require a regulator that connects to a standard cylinder valve using a Yoke or DIN interface, these three models are not suitable. None of the products we evaluated provide a Yoke or DIN connection, as they are designed specifically for low-pressure mask integration.

If you need a regulator capable of delivering the 350 bar pressure required for standard cylinder supplies, these options will not meet your needs. These are low-pressure second stage regulators, not high-pressure primary stages.