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

https://lima-wiki.win/index.php/I_Want_Faster_Results_%E2%80%93_Should_I_Combine_Threads_and_Ultherapy%3F

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for deep skin tightening, with results peaking around 3 to 6 months. RF heats the skin at 40 to 45°C to boost collagen more superficially and often requires multiple sessions