Ultherapy targets the deep 4.5 mm SMAS layer using ultrasound energy,...

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

Ultherapy targets the deep 4.5 mm SMAS layer using ultrasound energy, stimulating collagen over 3 to 6 months for gradual lifting. Compared to RF, which heats skin to 40-45°C mainly for surface tightening, Ultherapy offers deeper lift