I keep Tyvek coveralls in my bugout kit. I include some duct tape so I can cut the sleeves/legs to length and seal with duct tape. I can also make a belt from duct tape. Between these adjustments, I figure I can get a coverall to fit most people by carrying a single size. I could only find L and XL anyway.<br><br>I figured that they have good wind resistence and could be stuffed with newspaper or dry leaves, etc to make than insulated. Kind of a build your own down suit on site. In theory you could cut the suit in half and make a jacket and pants. The biggest problem would be ruining the zipper. More duct tape.<br><br>I also bought a few sets of the polypro painters coveralls. About half the cost of tyvek, not waterproof, and not particuarly durable. I was hoping they would provide cheap outer wear protection to help keep primary clothing cleaner and provide at least some (mininal) protection. They could be also be insulated and modified as described above.<br><br>As you mentioned, they are lightweight, low cost, easy to shrink via vacumn sealing, and fit a large variety of body sizes.