Provides the bases for a system of tolerances and deviations suitable for plain workpieces, and fits between mating cylindrical features or fits between workpieces having features with parallel faces such as the fit between a key and a keyway. Annexes give the basic equations and rules for establishing the system, examples of the use of the system and equivalent terms used in the Standard in eight languages. Identical with and reproduced from ISO 286-1:1988.