Ultra-thin wide field of vision with innovative direct sashing. The 2-eye mask is made to be extremely thin between the left and right eyes, and the frame is ultra thin for a stress-free vision that is just like a single eye mask. Diving Mask "Improve Vision" The worlds first D.S. "Direct Sashing System Structure" has brought one answer to the challenges that TUSA has been working for many years. Remove the inner frame that has been pressed around the left and right lenses to obstruct your field of vision, and fix the lens directly on the outer frame. It achieves an ultra-slim frame that has never been seen before, and has expanded the visible range of up and down to the left and right. In addition, the center frame portion that connects between the left and right lenses as far as possible, eliminating the feeling of splitting the left and right vision that is even the faults of the 2-eye mask. It is compact in size, but it has a stress-free vision that feels like a single eye mask. J spec skirt for Japanese people; Frame dimensions: 3.0 x 6.7 inches (75 x 171 mm); Hard case included; interchangeable prescription lens for myopia (MC-20)