inner and outer is silk.
The silk mask is with adjustable straps.
This silk masks are very fashionable and won't irritate your skin, unlike the disposable mask. It comes with a piece of PM2.5 filter which can use up to 7 days and throw it away after use and insert a new one! However, do take note that silk mask are more easily crumpled. Just wash , rinse and dry and steam it if needed!