The fly has a clear heavy plastic window that is welded (bonded) to the fly fabric. It cannot be opened. It is at the front of the vestibule.
A welded window is a "peek-a-boo" window (usually in the fly) to look out of and see what's going on outside ie.the weather, pack of wolves, etc.
It is melted onto the fabric. Unfortunately I have this tent and the window has completely detached making tent worthless until I can fix it somehow