Premium 9H Screen Slim Tough Tempered Gorilla Glass Film for Apple iPad 2 3 4 Tempered glass screen protector has high transparency, and the color never changes. The surrounding part is smooth to protect the screen from being broken. The product is environmentally friendly and pollution-free. Ultra-thin glass can be treated by high temperatures of 420. It has three layer, many kinds of thickness, hardness of surface: 8-9 H.