Hang the birdhouse on the wall or place on a shelf at home. Attach your keys to the ring & leave the sparrowin the birdhouse when you are at home. The sparrow keyringalso doubles up as a whistle. Complete with x 2sticky foam squares included for ease of fixing to the wall. Birdhouse measurements: (w) 7x (h) 7.5 x (d) 4.5 cm.