OTS Guardian Full Face Diving Mask

OTS Guardian Full Face Mask: A Purpose-Built Full-Face Mask for Serious Underwater Work

The OTS Guardian Full Face Mask is a complete diving system, not just a mask. It combines a full-face silicone skirt, a polycarbonate visor, and an integrated balanced second-stage regulator into one unit that covers your entire face and delivers air directly inside the sealed space.

If you are working in public safety diving, search and rescue, military operations, or any environment where you need reliable underwater communications, hands-free breathing, or protection from contaminated water, the Guardian was designed with you in mind.

Recreational divers occasionally look at full-face masks out of curiosity. That is worth addressing honestly: the Guardian is categorized under scuba, military, and rescue use. It is not a casual upgrade from a standard mask and regulator setup. It rewards divers who have a clear operational reason to use one.

The Seal: Where OTS Started the Design

Most full-face mask problems trace back to the seal. A poor seal wastes air, lets water in, and destroys the acoustic environment needed for clear underwater communication.

OTS addressed this directly with a double-seal skirt made from 55-60 Shore A liquid silicone. Shore A hardness in that range is firm enough to hold its shape under pressure but soft enough to conform to your face. The double-seal geometry means there are two contact surfaces working together rather than one.

The skirt geometry was also specifically designed to accommodate narrower faces, including slim temple areas, where many full-face masks fail to seal reliably. If you have tried other full-face masks and struggled with leaking at the temples, this is the design detail most likely to make a difference.

Equalizing: A Real Challenge, Honestly Addressed

Equalizing your ears, clearing the pressure difference as you descend, is something every diver manages with a standard mask by pinching the nose through the skirt. With a full-face mask, your nose is sealed inside the airspace, which changes how you equalize.

OTS does not pretend this is a non-issue. The Guardian ships with an equalizing kit that includes two different bases and interchangeable pads. The standard base can be repositioned up or down to suit your face geometry. If that base does not work for you, the second base with its pad options gives you another configuration to try.

This is a practical acknowledgment that one setup does not fit every face. Having the kit in the box means you can work through fit without ordering additional parts.

The Integrated Regulator

The Guardian does not accept third-party regulators. It uses a custom balanced downstream demand valve second stage designed specifically for this mask. The housing is glass-filled nylon for impact resistance. It connects via a 32-inch (81.3 cm) low-pressure hose with a 3/8-inch thread.

A balanced demand valve means the breathing effort stays consistent regardless of tank pressure. As your cylinder empties, you will not notice the regulator becoming harder to breathe from. That consistency matters when you are working hard underwater.

The second stage is designed to be removed easily. For a full-face mask, this is genuinely important. Cleaning and inspecting the regulator properly requires access to both the regulator and the interior of the mask. A removable second stage makes that routine rather than a chore.

The Ambient Breathing Valve

The ABV-1 Ambient Breathing Valve lets you breathe surface air while the mask is on your face, without drawing from your cylinder. On the surface, you rotate the valve counterclockwise to open a one-way inlet. Exhaled air is routed out through the second stage, not back through the inlet valve, which prevents carbon dioxide buildup inside the mask.

When you descend, the slight positive pressure inside the mask forces the valve closed automatically. If you forget to close it manually before going under, the valve disc provides a backup barrier against water entry.

In practical terms, this extends your cylinder supply during surface intervals and pre-dive checks, which adds up over a working dive day.

Fit and Adjustment

The Guardian uses a 5-point spider strap system. Five attachment points distribute the clamping force across more of your head than a standard two-strap setup, which reduces pressure hot spots and helps maintain the seal as depth changes cause the skirt to compress and release.

The buckles are made from a tough polymer compound rather than metal, which eliminates rust as a failure mode. If a buckle does break, OTS designed them to be individually replaceable rather than requiring strap assembly replacement.

Frame and Visor

The frame is glass-filled nylon, the same material used in the regulator housing. It is rigid, resistant to impact, and does not corrode. The single front visor is polycarbonate, which is optically clear, impact-resistant, and standard for full-face mask applications where a glass lens would be a safety liability.

The single-window design gives you an unobstructed forward field of view without a center bar dividing your vision.

What Comes in the Box

• Guardian Full Face Mask with integrated second-stage regulator
• 32-inch low-pressure hose (3/8-inch thread)
• ABV-1 Ambient Breathing Valve
• Equalizing kit with two bases and interchangeable pads
• Carry and storage bag (420-denier ballistic nylon with mesh panels, drain holes, ventilation, dry storage compartment, grab handle, and shoulder strap)
• Owner's Manual

The bag is worth noting separately. It is built to store the mask in a position that keeps water from pooling inside the second stage, with ventilation to prevent mildew. For a piece of equipment that sees regular operational use, proper storage between dives extends service life.

Color Options

The Guardian is available in multiple skirt and frame color combinations. For public safety and rescue teams, color coding by role or team is a common practice, and the range of options supports that.

Who This Is Not For

If you are a recreational diver looking for a more comfortable or novel experience, a full-face mask adds maintenance complexity, requires specific equalization technique, and locks you into OTS-compatible regulators only. A standard mask and regulator will serve you better for general diving.

The Guardian is the right choice when you have a specific operational need: contaminated water protection, integrated communications, or a professional environment where hands-free breathing and a sealed facial system are requirements rather than preferences.