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

https://bizzmarkblog.com/is-ultherapy-fda-cleared-for-lifting-or-just-tightening/

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