The intense selective light of the L600 penetrates the skin and is absorbed by the melanin in the hair. This absorption heats the hair and the heat is transmitted to the nourishment structure of the hair: the follicle. This results in it being heated to a temperature of 70°C for a millisecond and it is thus killed. Hundreds of hair follicles are destroyed by each flash; the hairs then fall out in one to two weeks.