The Ino Mask is ideal for smaller faces with its One-Window design, a wide field of view, and low volume. Its comfortable for divers of any level and style. The Fabric Mask Strap adds a new level of comfort to the dive experience. Anti-slip grip and easy adjustment ensures a snug fit to the back of the head. The snorkel keeper ensures secure placement. Fabric Strap Features: Easy size adjustment. Anti-slip on the back of the head. With snorkel holder. Head Circumference Size: 500-650mm. Material: Polyester and Nylon. Mask Features: One-Window mask designed for divers with smaller face shapes. Wide field of view is achieved by placing the lens closer to the face. A low volume mask. Varied silicone thickness with a proprietary low-friction skirt surface of the fitting line. Similar fitting technology as the popular INTEGA and ZENSEE. 3D SYNC Technology Round Edge Skirt Swift Buckle 3D