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

https://wool-wiki.win/index.php/Are_Thread_Lifts_More_Predictable_Than_Energy-Based_Devices%3F

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten over 3 to 6 months. RF heats skin to around 40-45°C for gradual collagen boost but works more superficially