4D firm serum for skin that is full of firmness and moisture. For skin that maintains radiance. 4D firmness serum for bouncy and moist skin. A uniquely developed process focuses on the raised muscles that lift the skin from the inside of the face and leads to firmer and more beautiful contours. 4D is a unique idea that not only leads the skin to beautiful facial lines, but also refines the surface of the skin and leads the appearance to a firm impression