Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer for a deep...
https://www.stealth-bookmark.win/ultherapy-uses-focused-ultrasound-targeting-the-4-5-mm-smas-layer-for-natural
Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer for a deep lift, with results peaking around 3 to 6 months. RF heats skin to 40-45°C for collagen boost but doesn’t reach as deep. Standard HIFU is quicker but less precise than Ultherapy