Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer deep under...

https://trulyexpatlifestyle.com/non-surgical-skin-tightening-in-singapore/

Ultherapy uses focused ultrasound to target the 4.5 mm SMAS layer deep under your skin, stimulating collagen over 3 to 6 months for natural lift and tightening