Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, reaching...

https://tiny-wiki.win/index.php/Ultherapy_vs_Standard_HIFU:_What_Did_the_2024_Study_Say%3F

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, reaching deeper than most RF treatments, which heat skin between 40 to 45°C for collagen boosting. Compared to standard HIFU, Ultherapy offers more precise energy delivery