Secure tempered glass lens with nose cover for nasal breathing swimmers - The diving mask features a tempered glass lens and a nose cover designed for users who prefer to breathe through the nose while swimming. - High-precision adjustment knob for lens strap tuning to prevent the mask from slipping off during activity. Environmentally friendly materials and durable construction - Silica gel based components are non-toxic, tasteless, soft and comfortable against the skin. - PC frame provides no deformation, and is stronger and lighter for reliable performance. - Anti-slip buckle uses a professional concave-convex design for easy adjustment, ensuring grip and stability in use. Comfortable fit and flexible sizing - Silicone band offers good elasticity and craftsmanship with a healthy, safe material. - The mask uses soft, food-grade liquid silicone that is eco-friendly and safe. - Lightly adjustable buckles and a flexible facial edge are designed to fit nearly any face shape and head size across multiple sizes. Water management and breathing performance - Two-way waterproof valve automatically closes when submerged to help prevent water ingress. - Fully dry anti-wave head with an automatic water-stop system increases safety and promotes calmer breathing; when waves rise, it helps prevent water from entering the airways. Use scenarios - Pool lap swimming and water aerobics where nose breathing is preferred. - Snorkeling in calm coastal waters or reef environments for extended wear. - Open-water swimming and travel, with sizing designed to fit a wide range of faces and head sizes. Key attributes - Function: secure lens, nose-friendly design, high-precision strap adjustment, two-way water-tight valve, auto water-stop system. - Compatibility: available in multiple sizes to fit most face shapes and head sizes. - Material: tempered glass lens, food-grade liquid silicone, silica gel components, PC frame. - Performance: non-slip, stable fit; improved comfort, reduced water ingress, and calmer breathing in waves.