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

https://archeredxm754.timeforchangecounselling.com/does-ultherapy-help-with-skin-texture-or-only-lifting

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to encourage gradual collagen tightening, with results peaking around 3 to 6 months