Songbird Essentials Window Bird House Decorative Feeders Outer diameter of flange is

Outer diameter of flange is 1-1/2" and inner diameter of flange is 1-1/4"

and convenient clean-out door on back

Landlords merely twist off the cap for nest checks

Opening is 2 1/2 inches

Tri-Tel Pole is exactly what you need to support your S&K Purple Martin House

Songbird Essentials Window Bird House Decorative Feeders Outer diameter of flange isWatch nesting activity unfold from your window with this cedar bird house. The clear plastic back panel lets you observe nest building and chick rearing up close, while suction cups secure it safely to your exterior window. Cedar construction resists weather, the PVC foam roof adds durability, and ventilation gaps keep the interior comfortable. A privacy shield slides over the viewing panel when birds need undisturbed rest. Drainage gaps prevent water