Keeps Your Purple Martins Comfortable This one-piece textured aluminum porch clips over the bottom of the crescent entrance hole, allowing easier access by martins, while still resisting most starlings. Permits martins to sit directly in front of their entrance hole, where they can keep an eye on their nest and the outside world at the same time. Easy Installation Dimensions 2.5 L x 2.5 W 1 Porch Per Order Only Fits Crescent Gourds In Stock-Ships Fast BASGPORCH 645194543225