We cannot determine the exact number of sessions required at the start, because each person has a different physiognomy depending on the hairiness, density and color of the hairs, generally the number of treatments varies between 8 and 12 sessions at intervals of 6 to 8 weeks or so. The clinical study carried out with the F1 diode has shown that a series of treatments allows on average to obtain a definitive reduction of 80 of the hair follicles between 8 and 12 sessions at intervals of approximately 6 to 8 weeks. The clinical study carried out with the F1 diode has shown that a series of treatments allows on average to obtain a definitive reduction of 80 of the hair follicles. pileux.