Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a deeper...

https://scarlettssuperbnews.inkharbory.com/posts/what-is-the-safest-way-to-compare-clinics-offering-ultherapy-in-singapore

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer for a deeper lift compared to standard HIFU, which usually targets 1.5 to 3 mm skin layers. Radiofrequency heats tissue to around 40-45°C to boost collagen more superficially