The design of this pencil case is inspired by a page of Paul Gauguin's drawing book, "Noa Noa". Tyvek is a brand of flashspun high-density polyethylene fibers, a synthetic material; the name is a registered trademark of DuPont. The material is very strong; it is difficult to tear but can easily be cut with scissors or a knife. Water vapor can pass through Tyvek, but liquid water cannot. All of these properties make Tyvek useful in a variety of applications.