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

https://zulu-wiki.win/index.php/What_Areas_Should_I_Avoid_Treating_Aggressively_Because_of_Nerves%3F_A_Practical_Guide_to_Ultherapy_and_Ultrasound_Lifting_in_Singapore

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a precise, deeper lift, with results peaking around 3 to 6 months. In contrast, RF heats skin to 40-45°C to boost collagen at shallower depths for gradual tightening