Yes it is real silk.

Our materials are Thai Tuan Pure Silk, the highest quality silk made by Thai Tuan.

They are one of Vietnam’s leading suppliers of silk.

Here are some sources for your reference:

• https://thaituan.com/vai-thoi-trang/thai-tuan-pure-silk
• https://www.youtube.com/playlist?list=PLsX5KIJ6XGFmnYRRhiwSeSeEsbMKhUxLz