Most Schwer cuckoo clocks are handcrafted from good quality wood. Traditionally, the trunk of the Lime tree, or Maple tree, is used in the clock making, as these woods can be easily carved. All the clocks feature the famous cuckoo call. This distinctive sound is made by air chambers, which squeeze air through a whistle. Two bellows are used to produce both sounds, first comes the “cu” and then the “cukoo”. Many traditional clocks have the cuckoo birds with moving wings as well. Others usually feature eagles, sparrows or owls.