After filling the chin, two splayed lines appear on the corners of the mouth.

Double chin. With the passage of time, years have brought old faces to people, among which the eight-character pattern appears in the corners of the mouth. The figure-eight pattern is caused by double chin, so it is necessary to strengthen the muscle strength of chin and remove double chin. The figure of eight refers to the nasolabial groove extending down from the root of both nostrils to the corner of both eyes. Because the image of this pattern is more like a figure of eight, it is commonly known as a figure of eight.