Plasma, “the 4th state of matter” is a visible flow of energy that travels through the air. Plasma is common in nature and is known from, for example, static energy or lightning. PlexR uses plasma in a dosed way to give controlled energy pulses to the skin. The energy pulses do not penetrate deeper than the superficial layer of the skin and then automatically become inactive. When touching the superficial layer, the energy is converted into heat, after which the upper layer of the skin evaporates. In the deeper layers of the skin, cell renewal is stimulated and a shrinkage of the collagen and elastin fibers occurs, making the skin tighter.