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

https://www.active-bookmarks.win/ultherapy-uses-focused-ultrasound-to-target-the-4-5-mm-smas-layer-which-few

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer deep under your skin, reaching where threads or RF can’t, for a natural lift. RF heats the skin to 40–45°C, boosting collagen closer to the surface