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

https://rylansultimatethoughts.talesignal.com/posts/is-there-downtime-after-a-thread-lift-in-singapore

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer to lift and tighten deep tissues, with results peaking around 3 to 6 months. RF heats skin to 40-45°C to stimulate collagen closer to the surface, ideal for mild tightening