Tombak is a chalice-shaped drum carved from solid mulberry wood. It is covered at the wide end by a membrane of lamb or goat skin. The technique of this instrument uses both hands and consists of rolling and snapping the fingers in various ways.
The Tombak is made in different sizes and the diameter of its large opening varies in different sizes from 20 to 28 cm. Tombak is one of few Iranian instruments which are decorated and much time and money are spent for decorating it.