Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer, offering...

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

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer, offering deeper lift than standard HIFU or RF, which heats skin to around 40-45°C for collagen boost. Thread lifts mechanically lift but results show immediately and may last a year