The ability to work specifically in the deep dermis, without damaging the epidermis, is regulated in the RF Secret by the delay time of fractional radiofrequency. The needles are inserted at a rate of milliseconds equal to a stamping process in the skin and also withdrawn immediately. Only after the needles are penetrated into the desired skin layer, is carried out for a few milliseconds, a radio frequency pulse to set heat damage. While the penetration into the skin, the needles remain always cold. In order to achieve a deep and superficial effect, the needle depths can be varied individually in the respective treatment passes.