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

https://technivorz.com/why-is-imaging-such-a-big-deal-in-ultrasound-skin-tightening/

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, reaching deeper than most RF treatments that heat skin to around 40 to 45°C. Compared to standard HIFU, Ultherapy delivers more precise energy for lifting