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

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

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten over 3 to 6 months. RF heats skin to around 40-45°C for gradual collagen boost but works more superficially