Hi Mary. A bunk feeder is a Polypropylene trough used to feed animals on farms. Basically a plastic 10 foot long trough you can put water, hey in there for the animals. They are pretty tough and very light weight. Being a software developer I had no idea either until someone here posted the idea. I went to a local farm feeder supply store near by and took the chance on ordering two of them since 120 dollars seemed like a reasonable gamble. Will they work? I think so, nice and light, waterproof. They should hold up to UV exposure. The fiber glass covers I made display my lack of skill in that area, but they work.