Tempered glass is a hardened glass, specially designed to cover and protect the phone screen from scratches and other damages. It does not affect the functionality of the screen. In case of phone drops, there is no guarantee that the screen will not be damaged, but it offers additional protection.
It is of the UV Liquid type, a relatively new kind of tempered glass consisting of an adhesive that spreads evenly over the entire surface of the phone screen, even into cracks. The hardening of the adhesive is done with the help of a UV lamp. The process takes more time compared to classic protections and must be done according to the manufacturer's instructions for the best possible result.
It is compatible with the Galaxy S23 Ultra.