A few months ago I ordered a pair insulated rubber boots. In the winter, regular rubber boots are just plain frigid no matter how many pairs of socks you wear. My usual pair of boots is the cheapest model and I have to wear 2 pairs of fluffy socks no matter what. That's because I would get blisters within 30 minutes of wearing of them. Good times in the hot and humid summer!!!! Granted they are made of a tougher pvc type rubber, so that's probably why they are so hard on my feet. I was all excited about this new pair, but then I realized that I couldn't get my feet out of the boots if I wore two pairs of socks...no matter what thickness. I was worried that I would instantly get blisters. But no! My feet have stayed toasty, blister free, and comfortable. I think it is because they are made of a softer rubber and have support inside.