The tempered glass is a hardened glass, specially designed to cover and protect your phone's screen from scratches and other damage. It does not affect the screen's functionality. In case of a phone drop, it does not guarantee that the screen will not break along with it, however, it is an additional protection. It is 2.5D, which means its perimeter has rounded edges for a smoother touch feel when using the screen. Useful for modern smartphones with curved screens. It is compatible with Galaxy A12.