This International Standard specifies the marking System recommended to the manufacturer so as to reduce risks of incompatibility between components of bicycles produced according to new ISO Standards and traditional components. This Problem of selection of the appropriate component will make itself felt above all at the level of the repair of bicycles and the distribution of spare Parts; it will be necessary for this distinguishing mark to be : - universal, i.e. understandable by users and repairers in all countries, - standardized, i.e. the same sort of mark for all cycle components, - practical, i.e. easy to apply and visible on all the components concerned.