The celesta /sɨˈlɛstə/ or celeste /sɨˈlɛst/ is a struck idiophone operated by a keyboard. It looks similar to an upright piano (four- or five-octave), or a large wooden music box (three-octave). The keys connect to hammers that strike a graduated set of metal (usually steel) plates suspended over wooden resonators. Four- or five-octave models usually have a pedal that sustains or damps the sound. The three-octave instruments do not have a pedal because of their small "table-top" design.