I've tried other "no show" socks for my flats & these work great.  I cannot see them in my flats & they stay put with the help of the silicone patch on the heel.  I was afraid the little non stick pads on the bottom of the socks were going to bother me but luckily they do not whatso ever.  I am glad I got some - will be getting more as flats are my main go to shoe!