 Staves with a neutral clef do not always have five lines.Commonly, percussion staves only have one line, although other configurations can be used.The neutral clef is sometimes used where non-percussion instruments play non-pitched extended techniques, such as hitting the body of a violin, violoncello or acoustic guitar, or where a vocal choir is instructed to clap, stomp, or snap, but more often the rhythms are written with X marks in the instrument's normal stave with a comment placed above as to the appropriate rhythmic action.