I wonder...

...Who Melissa & Doug are catering for.
They have addresses and phone numbers in USA, Canada, Mexico and UK.
It's another Christmas present from WAY back, which I finally got around to making.

Immediate thought - - - "I could back a bus through that hole, well a Starling at least."
Having checked, apparently not, but nearly two blue-tits side by side at 40mm.

My check found:-
"The entrance hole size depends on the species you hope to attract:

25 mm for blue, coal and marsh tits;

28 mm for great tits, tree sparrows and pied flycatchers;

32 mm for house sparrows and nuthatches; 
45 mm for Starlings.
Or
40mm for some odd, or American, beastie? Or a Starling with anorexia? I'll just bung it up somewhere and see if anybody shows interest.
That said, and having seen the way Starlings can squeeze into my column holding fat-sticks I reckon they could manage 40mm, I'll measure the gaps tomorrow.
I have NO idea what that piece is with red lettering on, it's a bit sticky, but tells me NOT to eat it - ASIF!

I also notice, retrospectively, there's no perch at the front door.
;¬)