Ultherapy uses ultrasound energy targeting the 4.5 mm SMAS layer to stimulate...

https://www.alphabookmarks.win/ultherapy-uses-focused-ultrasound-to-target-the-4-5-mm-smas-layer-stimulating

Ultherapy uses ultrasound energy targeting the 4.5 mm SMAS layer to stimulate collagen deep under the skin, with results peaking around 3 to 6 months