I bought Korkers about 3 years ago. I have the felt, felt with studs and the lug sole. This year I was fishing in the White River and my feet suddenly felt like I was carrying a load of weeds on them. Only after i got out of the water did i notice the felt soles had seperated from the insert piece. Now i was a bit upset and called the Korker customer service and told them what the problem was. They asked as to when i had purchased them and i told them. He told me the first version had only glue on them. He then gave me a confirmation number and told me to send them back. I did and they sent me back a new set of soles that has brads holding the flet to the inserts. FREE !! Yep I love my Korkers.