Tread plate, not thread tape. The OP is talking about the plastic diamond plate used to protect the front of the trailer from stones and other road debris. He got the term from the fact that diamond plate was originally designed to be used to provide a solid metal surface with added traction for walkways, steps, etc. For some odd reason, many people feel it is more attractive than a flat surface and like to use it for tool boxes, etc. (I personally feel it looks too industrial but, obviously, I'm outnumbered).