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

https://cruzinnp079.tearosediner.net/what-is-the-difference-between-dermal-tightening-and-lifting-outcomes

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten skin, with results peaking around 3 to 6 months. Compared to RF, which heats tissue to 40-45°C for collagen boost, Ultherapy offers deeper muscle-layer stimulation