M-23 
- A 200% increase in field of vision (compared to traditional two-window masks) has been achieved by reducing the distance between the eye and lens.
- A TUSA-exclusive five-position strap angle adjuster allows for easy adjustment and perfect fit.
The best way to increase the field of vision in a compact design is to shorten the distance between the lens and the eye. However, this has been limited by the narrowness of the area between the lenses because of the height of the bridge of the nose. In the M-23, the lenses have been spread apart, making it possible to get them closer to the eyes and to fit the nose skirt snugly into a thin frame between the lenses. Compared with conventional two-lens masks, the M-23 has double the field of vision. This design also allows convenient access to the nose for easier clearing of the ears. Moreover, the short distance between the lens and the eyes enables more accurate framing during underwater photography.
| |  A new product to answer the growing demand for underwater photography.
The M-23 is the optimum product for divers who wish to enjoy underwater photography. The new construction means the entire mask frame is closer to the face, so that when the diver focuses the camera, it feels closer to how it does with the naked eye. The M-23QB has particularly concentrated on the viewfinder, enabling the shutter to be released accurately. It also offers outstanding performance for video camera users. M-23QBIn black silicone and with a super-thin form for underwater photographers, this design features a black silicone skirt and strap. |
Features of M-23
The space between the left and right lenses on conventional masks is narrow, so to avoid making contact with the upper part of the nose, the entire mask frame must be suspended slightly away from the face. As shown in photo 1, the area between the lenses on the M-23 is wider, enabling the entire mask frame to be moved closer to the face without touching the bridge of the nose.
Photo 1
 | | Photo 2 shows a horizontal view of a conventional mask and the M-23 with the nose section on top and the skirt below. For the distance indicated by the arrows, the entire mask frame of the M-23 is closer to the face. In other words, the distance between the eye and the lens has been minimized, producing a wider field of vision. |
In addition, this allows the diver to look unobstructed through the viewfinders of underwater cameras and video cameras.
 The field of vision angles obtained by the measuring instrument shown in photo 3 are converted into two-dimensional areas and are compared, in illustration 1. From this comparison, you can see that the M-23 has more than double the field of vision of conventional products. 
Photo 3 |
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Five-position strap angle adjuster
The M23 is equipped with the top class strap adjuster used on the M-14. The strap angles on both the left and right sides can be varied, and then secured with the adjuster. This enables the up/down and left/right pressure on the face to be delicately adjusted.
