Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, stimulating...

https://mike-wiki.win/index.php/Ultherapy_vs_Thermage_for_Jowls_%E2%80%93_Which_One_Actually_Lifts%3F

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer, stimulating collagen deep beneath the skin. Unlike RF that heats surface layers to 40–45°C, Ultherapy works deeper for a gradual lift over 3 to 6 months