Ultherapy targets the 4.5 mm SMAS layer with ultrasound energy, reaching deeper...

https://hectorsmasterinsight.novacrestiq.com/posts/how-many-ultherapy-treatments-have-been-done-worldwide-unpacking-the-global-track-record

Ultherapy targets the 4.5 mm SMAS layer with ultrasound energy, reaching deeper than most RF treatments, which warm skin between 40 to 45°C but mainly affect the surface