These stay on and are comfortable! I wasn't certain as to whether the silicone would rub or be uncomfortable - I don't even feel it, but it definitely does its job well! These are thin, which is perfect during the summer under tennis shoes. They have gone through washings well and still stay up on my heel where they should be. Even after wearing them all day they are in place and comfortable. These are no-show for tennis shoes and others that have a bit of a "top," but not for shoes which barely come above your toes. I'd definitely buy more of these again!