The tempered glass by Volte-Tel is a hardened glass, specially designed to cover and protect your mobile screen from scratches and other damages. It does not affect the functionality of the screen. In case of a mobile drop, it does not guarantee that the screen will not break along with it, but it provides additional protection. It is 2.5D, which means that 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 the TCL 20R.