Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a deeper...

https://reidscoolthoughtss.swiftnestly.com/posts/what-does-a-proper-assessment-look-like-before-skin-tightening

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a deeper lift, with results peaking around 3 to 6 months. Radiofrequency heats skin to 40-45°C to boost collagen, offering gentler tightening but at a shallower depth