Ultherapy uses ultrasound to target the 4.5 mm SMAS layer, making it popular...

https://bravo-wiki.win/index.php/If_I_Did_HIFU_Before_and_Saw_Nothing,_Should_I_Try_Ultherapy_Next%3F

Ultherapy uses ultrasound to target the 4.5 mm SMAS layer, making it popular for lifting deep tissue without cutting. RF heats skin to around 40-45°C to boost collagen, great for mild tightening