Its just thick foam like youd find in most Walmart slippers. I bought this headset for my son who games constantly and chats with all his friends online while gaming. Compre tres pares con eso les digo todo la calidad es la mejor que alguna vez haya visto en chanclas . I?d like to see a kicker comp series and might by. These headphones push out exceptional sound quality. Something a bit different to add to my large collection of FitFlops. But, for now its a go. They had a lot of very visible glue where the insole meets the plastic sole and there were cracks in the plastic all around where the metal stud in the heel is. Good for around the house and property. With all that said, I will wait to see how my legs feel after wearing them for a week or 2.