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

https://shed-wiki.win/index.php/Why_Does_My_Jawline_Look_Softer_Even_If_My_Skin_Texture_Is_Fine%3F

Ultherapy uses focused ultrasound to target the deep 4.5 mm SMAS layer, encouraging natural collagen over 3 to 6 months for gradual lifting. Compared to RF, which heats skin surface to around 40-45°C, it's deeper but less immediate