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

https://blast-wiki.win/index.php/Is_It_Normal_for_Results_to_Be_Progressive_After_Ultherapy%3F

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