These birdhouses are 100% reclaimed wood. They are simple to hang with one screw in the back. They are mixed species birdhouses. The natural twig for a perch gives it a nice touch. They are finished with 3 coats of a natural stain, poly mix which penetrates deeply into the wood for excellent protection. These houses have a 5 x 5 floor and we have two heights available (the houses shown stand about 11 1/2" tall). They have a removable floor for easy cleaning if necessary (birds typically clean it out). These birdhouses should give you many years of bird viewing enjoyment. If you have a specific size you would like feel free to contact us.