Ultherapy targets the deeper 4.5 mm SMAS layer using focused ultrasound for...

https://bizzmarkblog.com/is-ultherapy-fda-cleared-for-lifting-or-just-tightening/

Ultherapy targets the deeper 4.5 mm SMAS layer using focused ultrasound for gradual tightening, with results peaking around 3 to 6 months. RF heats skin to 40-45°C for surface collagen boost but doesn’t reach SMAS