Ultherapy uses focused ultrasound energy to target the 4.5 mm SMAS layer deep...

https://wiki-view.win/index.php/What_Does_%E2%80%9CStructural_Lifting%E2%80%9D_Mean_in_Non-Surgical_Treatments%3F

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