ISO 6699:2016 specifies the dimensions and tolerances to ensure secure assembly between the stem and the handlebar centre of a bicycle.

It is applicable for bicycles intended for use on public roads, and on which the saddle can be adjusted to provide a saddle height of 635 mm or more.

It is not applicable for specialized types of bicycle, such as tradesmen's delivery bicycles, tandems, toy bicycles and bicycles designed and equipped for use in sanctioned competitive events.