Terahertz Beauty Facial Roller Double Head The rollers can be used in different sizes, making them convenient!! Also for the face and neck! Terahertz waves, which emit a frequency of 1 trillion times per second, are said to have various effects on the human body and substances. Terahertz waves, which have the effect of promoting blood circulation, are expected to improve stiff shoulders and neck fatigue. ※ Please note that there may be small scratches or dents. ※ The color of the stone may slightly change depending on the environment. The images are of the actual product. ※ The way people feel the effects of power stones varies from person to person, and it does not necessarily mean that they will be effective.