This specific style of case is often sold as a "generic" or "Skin Touch" model and features several key characteristics:
MagSafe Compatibility: It includes a built-in magnetic ring on the back, allowing it to work with MagSafe chargers and accessories.
Matte Texture: The case has a frosted, anti-fingerprint matte finish, often described as having a "bare machine" or soft-sanding feel.
Protective Design: It typically features precise cutouts for the S21 Ultra's camera module and raised bezels for extra screen and lens protection.