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

https://future-wiki.win/index.php/Is_Ultherapy_Backed_by_Real_Studies_or_Mostly_Marketing%3F

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, unlike RF which heats tissue around 40 to 45°C without deep reach. Standard HIFU often doesn’t go as deep as Ultherapy or is less precise