Mares X-Vision Liquid Skin Two Window Mask is a great choice for vision underwater. With the addition of Mares patented Liquid skin technology, the X-Vision now offers comfort that was formerly impossible. By co-molding two different types of silicone, there is no longer a need to compromise comfort in order to support the frame structure of a mask. The support structure and the area of the seals are molded with a silicone that is 30% harder than the traditional material. The extremely soft silicone portion rests on the face delivering a new level of comfort.The marks that are typically left on your face after a dive are mostly eliminated. The superior elasticity and softness of Liquid Skin allows the mask to fit perfectly on a wider range of faces. Liquid Skin adapts to facial movement and offers a great seal virtually eliminating water leakage. Equalization is now much easier due to the super soft nose pocket. Its light weight and soft adherence to the face are so gentle that you can forget you"re wearing it X-Vision Liquid Skin is the ideal mask for all kinds of diving, from snorkeling to free diving to scuba, both for recreational and professional divers.By attaching the buckles to the skirt masks have superior hydrodynamics because the strap fits closer to the head, making this a medium volume mask, in addition the tension exerted by the strap acts on the skirt and not directly on the frame reducing the pressure of the frame against the face.The Ergo Buck