As for the external devices they pretend that through transmitting some kind of energy (laser, radio frequency, micro current ultrasound etc)  they can tighten the skin or regenerate its components. That assumption do not resist to scientifically designed study when we compare a side to another. Best case scenario the improvement is of 20 % with a response of 1 patient in 5. So Facial treatment with external devices can be interesting if you are not expecting a significant change or a major improvement. As we see it every day in our consultations with disappointed patients, It doesn't achieve the goals it markets.