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

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

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten deep tissues, with results peaking around 3 to 6 months. RF heats skin to 40-45°C to stimulate collagen closer to the surface, ideal for mild tightening