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

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

Ultherapy uses focused ultrasound targeting the 4.5 mm SMAS layer, stimulating collagen deep under the skin for a natural lift