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

https://www.third-bookmarks.win/ultherapy-uses-ultrasound-energy-targeting-the-4-5-mm-smas-layer-to-stimulate

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, stimulating collagen deep under the skin for gradual tightening. It’s known for visible improvements over 3 to 6 months