The spring driven mechanism causes the heads and beaks of the birds to move at the rhythm of the whistling. The whistling is produced by small pipes and bellows driven by a spring mechanism. It has two positions of playing. Either continuous or with intervals.
The gilt brass case is surmounted by a suspension ring. One of the two birds is seated on top of a bar, the other on the velvet ground. The annular base is adorned with a high relief of foliate scrolls.