They look invisible but feel it too when you are wearing them but give that feeling of something covering your toes and bottom of the foot like a sock do.
On the back of the heal , just inside are 5 little silicon lines that you can't see or feel but stretch with the sock and help the sock stay in place so it doesn't slip off .
They are extremely lightweight and made of 85 % premium cotton keeping foot dry and comfortable
for more information or to purchase please click the link below
https://www.amazon.co.uk/Show-Socks-8BESS-Non-Slip-Grips/dp/B01KLVN9JQ