Lens Material: 4mm Thick Tempered Glass Mask Material: PVC Headband: TPR Material Steel Ring: Stainless Steel Frame Tempered Glass Lens Safety: Forget Fragile Plastic Lenses This is high quality tempered glass that resists scratches and shatters. Easy Adjustable Buckle: Just pull to secure the strap in the desired position and the buckle will hold the strap securely in place. Presto: Customized comfort. Rugged for Scuba Diving: Thanks to its sturdy construction, your mask can withstand all kinds of wear and tear - from snorkeling in the pool to scuba diving. Integral Lens: The snorkeling mask should help you see better, not obstruct part of your vision. Now you can clearly enjoy all the underwater scenery. Package includes: 1* diving mask