The open slot at the bottom is protected from predators by a wooden guard. The interior surface and landing platform is made of rough wood covered with black screening to make it easy for bats to cling when roosting and landing. An echolocation slot on each side of the home helps bats locate their home. Although designed for the Mexican free-tail bat, found predominately in the southern United States, this bat house is suitable for all species of small, insectivorous bats throughout North America and has been highly successful with the little brown and big brown bats.