This hand-crafted nestbox with slanted overhang is a perfect shelter for bluebirds or tree swallows. It features a 1.5" entry hole. The right-side door easily opens for seasonal cleaning, a single pin can be twisted to unlock and swing the door open. To lock, simple twist the pin. Providing a nestbox in your backyard will bring you seasons of enjoyment as you watch these beautiful birds raise their young. Its good practice to have them up and ready by March for bluebirds and May for swallows. It is often recommended to offer a pair of nestboxes, so the two species don't have to compete for ownership. In addition, swallows will protect the bluebird's home from other competitors.