Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to tighten...

https://www.bookmark-tango.win/ultherapy-uses-focused-ultrasound-targeting-the-4-5-mm-smas-layer-to-encourage

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to tighten skin deeper than RF and standard HIFU, which mostly warm surface layers around 40 to 45°C