Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for deep...

https://wiki-book.win/index.php/I_want_neck_tightening_but_not_surgery_%E2%80%93_Ultherapy_or_RF%3F

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for deep tissue lifting, with results peaking around 3 to 6 months