Ultherapy uses focused ultrasound energy to target the deeper 4.5 mm SMAS...
https://www.bookmarking-presto.win/ultherapy-uses-focused-ultrasound-to-target-the-4-5-mm-smas-layer-for-natural
Ultherapy uses focused ultrasound energy to target the deeper 4.5 mm SMAS layer, stimulating collagen over 3 to 6 months for gradual lifting. Compared to RF, which heats skin to 40-45°C mainly in the superficial layers, Ultherapy reaches deeper tissue