Ultherapy uses focused ultrasound targeting the 4.5mm SMAS layer, promoting...
https://bizzmarkblog.com/is-ultherapy-fda-cleared-for-lifting-or-just-tightening/
Ultherapy uses focused ultrasound targeting the 4.5mm SMAS layer, promoting collagen over 3 to 6 months for natural lift and tightening. Compared to RF which heats skin to 40-45°C mainly in the surface layers, Ultherapy reaches deeper tissues