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

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

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer, unlike RF which heats skin to 40-45°C for collagen boost. Standard HIFU often treats shallower layers. Thread lifts offer immediate lift but may carry more downtime