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

https://shanestue668.yousher.com/ultherapy-for-neck-and-lower-face-what-is-advanced-layering

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, which heats skin to 40-45°C mainly for surface collagen, Ultherapy reaches deeper layers