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

https://highstylife.com/thermage-vs-10therma-are-they-both-monopolar-rf/

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten deeper tissue, with results peaking around 3 to 6 months. Compared to RF that heats skin to 40-45°C for surface tightening, Ultherapy reaches deeper layers