Aquaseal works pretty well. But when my Neo's started leaking about 10 years ago I went to the local Scuba shop and bought some glue from them. This was the same glue used to put the waders and wetsuits together in the first place. It literally welds the rubber together behind the nylon. Using that stuff I never had a leak again. Unfortunately it got misplaced in the move a few years ago and now I need to go see if they still carry the stuff. I have no idea what it was but it looked and smelled just like the stuff you use for PVC Pipe. I have an old pair of waders that I want to put new soles on and this is the only thing I would trust them not to leak.