Rubber bands are very elastic, mostly thin caoutchouc bands in the shape of a ring. They are cut from rubber tubes in strips of different widths. Their cross section is therefore rectangular, in contrast to sealing rings, which have a round cross section. A distinction is made between rubber rings made of natural rubber and synthetic rubber. The former have an elasticity of up to 750%, are mostly safe for use in food and come from a renewable raw material (rubber tree). Synthetic rubbers have an elasticity of up to 350% and can fulfill certain properties, such as oil resistance or UV stability. They are produced petrochemically.