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

https://www.play-bookmarks.win/ultherapy-uses-focused-ultrasound-targeting-the-4-5-mm-smas-layer-for-a-deeper-1

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer deep under your skin, stimulating collagen over 3 to 6 months for natural lift and tightening