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

https://www.hometalk.com/member/254051008/alice1337254

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