I will not buy a blind with zip up windows or anything velcro anything any more. I know the thread is about a frozen entrance zipper as mentioned that can be an easy however minor detail. When all your window zippers are froze then you have trouble. The only zippr that should maybe be on a blind is the door the rest cause greif if you need another window and game is close. Double Bull probably makes the best blinds out there but they are more costly but worth the extra dollars in the end.