Bipolar molecule in the tissue,it is mainly made by water and protein.It gets into the deep skin through PSWD from the probe,but is doesn't hurt the cuticle. When the temperature arrive 39-42 centigrade.the collagen will be shrunk by heat, it can accelerate to made collagen. The efficacy can go deep into the derma 2-2.5mm,increase the activity of collagen makes your skin firm and elastic.