You mentioned the temples and the corners of the mouth, which can be used. The longest use time for the whole face is no more than 60 minutes. For people with thin stratum corneum and skin allergies, the probe should stay on each position of the face for no more than 3 seconds; for oily or neutral skin, the use time for each position can reach 5-8 seconds. This instrument must be coated with a medium when used. It is recommended to use your frequently used skin care products, such as lotion, aloe vera gel, etc. as a medium. (Alcohol-containing essential oils and fragrances should not be used)