A thumb piano, similar to the mbira. It consists of a number of metal or split cane tongues over a wood board or box. The tongues are held in position by a crossbar, with one end of each tongue free to be plucked - usually with the thumbs. Although occasionally found elsewhere, the sansa is primarily an African instrument. It is usually held in the hands or rested on the lap.

The pitch of a tongue is determined by its length, which can easily be altered by sliding the tongue back and forward under the lateral bar. The longer the tongue, the lower the note. Often the board or box is decorated by carving or painting and sometimes the sound is modified by wrapping wire around each tongue to produce a buzzing effect when plucked.