Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and...

https://www.random-bookmarks.win/ultherapy-uses-ultrasound-targeting-the-4-5-mm-smas-layer-deep-under-your-skin

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten deeper tissue, with results peaking around 3 to 6 months. Compared to RF, which heats skin to 40-45°C mainly for surface collagen, Ultherapy reaches deeper layers