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

https://griffinphut760.theglensecret.com/what-is-the-submental-area-and-which-treatment-targets-it

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