Ultherapy uses focused ultrasound energy to target the 4.5 mm SMAS layer deep...
https://highstylife.com/thermage-vs-10therma-are-they-both-monopolar-rf/
Ultherapy uses focused ultrasound energy to target the 4.5 mm SMAS layer deep under the skin, promoting gradual lifting over 3 to 6 months. Compared to RF heating skin to 40 to 45°C for collagen boost, Ultherapy reaches deeper layers