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

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

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, helping lift and tighten deeper tissues. In contrast, RF heats skin to about 40-45°C mainly affecting surface collagen