I bought a Gilberston a few years ago and have had chickadees and Prothonotary warblers use it. Since Mr. Gilbertson no longer makes them I made one of Fred’s Hexagon boxes (the smallest size) and painted it to look similar to a Gilbertson. It’s pretty close to being round inside.
When the new wears off the old shines through
When The New Wears Off The Old Shines Through.