Songbird Essentials SE617 Portal Protector 1 1/2 in (Metal) (Set of 1)

Kettle Moraine Copper Portal for Eastern Bluebird Bird Houses Predator Guard

Kettle Moraine Replacement Predator Guard with Copper Portal for Eastern Bluebird Houses 1 1/2" opening

Kettle Moraine Copper Portal for Bird Houses 1 1/8" Opening - Predator Guard

Songbird Essentials SE616 Portal Protector 1 1/4 in (Metal) (Set of 1)

Woodlink Wooden Bluebird House - Model BB1

Kettle Moraine Copper Portal for Bird Houses 1 1/4" Opening - Predator Guard

Perky-Pet 50301 Wren Home Cedar Birdhouse

Songbird Essentials SE615 Portal Protector 1 1/8 in. (Metal) (Set of 1)

Nature's Way Bird Products CWH1 Cedar Wren House, 8" x 8.875" x 8.125"

Nature's Way Bird Products CWH3 Cedar Bluebird Box House