The optimal mask to all people.

Features of flange

B.F.F.S. allows you to choice your best flange!

You can select the frame with designs, colors, and for purposes. Furthermore to fit your face, you can select from 4 type of flanges.
This is a limitation service at the exclusive dealers.  Please ask our customer support or the distributors of your region.

type-A (inner volume 60cc)

In order to reduce the inner capacity to the limit, the frame is positioned as close as possible to the face. This structure secures the widest visibility especially lower view compared with the type-C flange.
Its small inner volume of 60cc(*1) makes the buoyance also small, which together with synergy effect of the stabilizer structure and twin-curve-lip structure provide extremely stable fit in the water.
On the other hand, there is a case that it may not fit well because of individual difference in face shape and size.
Please try it on at a shop to confirm the fitting.
(*1) Based on our standard measurement method.

(Note) There is the case that a root part of the nose hits the frame part of flange, or there is another case that it is difficult to pinch the nose for ear clearing.

type-B (inner volume 85cc)

In case if the type-A does not fit well due to the shape un-match to your face, please use the type-B.
The frame position of the type-B is shifted forward by 4mm to expand the fitting range to various shape and size of faces while maintaining the fundamental characteristics of the type-A.
The stabilizer structure and twin-curve-lip structure are succeeded to the type-B to assure the stable and comfortable fit.

type-D (inner volume 95cc)

Best selling model of 2016-2017.

Incorporating the opinions of a wide range of other countries, has adopted to optimize the flange shape to fit in more widely with people of each country.
The type-D especially improves the fit around the nose, root of nose and forehead, so the type-D will fit in at a high probability even with the people who are not satisfied with the conventional flanges.

The surface plane is shifted by 5 degree toward downward compared with the type-A and type-B so that it improves the downward visibility of the abdomen to the feet. Moreover it gives a sense of more stylish appearance.

The double-lip structure has further evolved to the “advanced double-lip” structure with a larger arc cross-sectional shape which makes the pressure on the outer periphery of the face more gradually and progressively weaken toward outside, so that it hardly leaves marks on the face.

Optimizing the shape and length of the lip under the nose, to prevent displacement of the mask while effectively preventing the entry of water when pinch the nose for ear clearing.

Our patented technology “brilliant-and -smoke finish” has also further evoluted. The outside surface is matted finished for easy cleaning, preventing adhesion of dirt and Virile appearance.

type-C (inner volume 110cc)

The type-C design is more universal to suit everyone, which has been adopted since the introduction of bio-metal mask. Its merits are, soft fit and ease of ear clearing.
It will ensure effective wide field of view to the traveling direction in the water as the lens surface plane is set toward slightly upward.

The type-C is the first launch of the flange in the bio-metal series and it has been the best-selling design.

The outside surface is matted finished for easy cleaning, preventing adhesion of dirt and Virile appearance. (2017 New)


Double-lip Structure

A lip is the periphery of the diving mask flange in contact with the face. The double-lip structure has one additional lip toward inside of the flange in addition to the conventional lip that is structured toward outside of the flange. The double-lip structure doubles the total area in contact with the face, and consequently it reduces the contact pressure to the face and improves the waterproof.

Advenced double-lip Structure

The “advanced double-lip” structure has a larger arc cross-sectional shape periphery which makes the pressure on the outer periphery of the face more gradually and progressively weakened toward outside, so that it hardly leaves marks on the face.

Stabilizer Structure

The flange of the stabilizer structure wraps the frame around the lower and side surfaces of the frame. This structure has overcome the weakness of conventional shaped flange which tends to bend from the root of the connection portion with the frame. As a result of this overcome, the stabilizer structure has achieved very stable mounting while the inner volume remains as minimum.

In the type-B, supporting the frame back effectively in a wide area the to secure the similar effect.

Twin-curve Structure

The curved circumferential surface effectively use different curves at the inner and outer surfaces so that the periphery gradually changes the thickness of the cross section. This structure optimally controls the amount of the bend and contact pressure of circumferential surface when mounting.

Brilliant-and-smoke Finish (type-A, type-B, type-C Clear)

The Inner surface is matte finished while it remains silky gloss outer surface. This brilliant-and-smoke finish gives an elegant smoked appearance and suppression of an external coming light with the clear color flange, and suppression of internal reflection which is helpful for a photo shooting with the black flange.

Matt Finish (type-D, type-C Black)

It is matt finished black on both inside and outside. It is the best suited diving mask for those who dives under the situation where any reflection of light is inherently prohibited or undesirable. Its gives a dignity of the professional tool and protection against adhesion of dart.

Wide vertical view

The frame is tilted downward by further five degrees compared with type A and B, and the lens frame is set as close as possible to the forehead. With this structure has gained downward field of view and consequently achieves wider vertical field of view.

Super fit

It is designed to fit more diverse face types compared to other models by selecting material and optimizing size and shape of area fits to the face. Its wearing feel is very soft and better to get used to.

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