I. Principle of hair transplantation Select the whole layer of skin with hair in appropriate parts of the body, separate it into single or multiple hair units, transplant the hair units to the parts that need to be transplanted, such as head, eyebrows, etc. through fine microsurgery techniques, and let them survive and grow in the new parts, so as to achieve the purpose of replenishing the number of hairs and modifying the local hair distribution pattern, so as to achieve the cosmetic effect. 2. Suitable for people 1.Poor hair or hair loss