When exposed to a laser, the hair follicle is gradually heated using low energy, but with a high repetition rate – 10 Hz 10 times in 1 sec. The laser beam penetrates through the skin surface to the hair follicle. The luminous flux is absorbed by the melanin of the hair follicle and turns into thermal energy, destroying it without damaging neighboring tissues. These actions prevent progressive hair growth in the future. The Hair W ICE device has a built-in semiconductor cooling system. Water passes between the bars of the diode laser, cooling the tip to -10 °C.