Its a galvanized type roll of sheet metal which you can cut & bend with a razor knife. Very east to work with. You will find it in the gutter section of Home Depot. One problem I found. Some water still drips down the beams, which I did not cover. So, I am about to cover the beams with the same sheet metal running into the installed gutter. I covered the ground with the 4x8 $5 glued boards over cement bricks. As far as the mice & other unfriendly guests, you may want to get a cat.