Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a precise...

https://lunasbrilliantdigests.evergrovio.com/posts/how-do-i-know-if-i-need-surface-tightening-or-structural-lift-2

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a precise lift that works deep under the skin