Watch a family of birds up close! Attaches to window with suction cups and allows you to observe nest-building. Witness the miracle of eggs hatching or watch as Mama feeds her young. Each bird house comes pre-assembled. Wooden Nest View Bird House. Includes clear acrylic back that attaches to window with 2 suction cups. Measures 8"H x 5.5"W x 4"D. Entrance hole measures 1.5". Made out of cedar.