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

https://cruzqmfp756.theburnward.com/what-age-is-best-for-rf-tightening-focus-on-your-30s-to-early-40s

Ultherapy uses focused ultrasound targeting the deeper 4.5 mm SMAS layer to stimulate collagen over 3 to 6 months, offering gradual lifting without downtime