The reference manual describes the main criteria and methods for selecting fits for cylindrical and conical joints, rolling bearings, threaded (metric, trapezoidal, thrust, round, pipe threads), spline and key parts. Practical recommendations and examples of calculation and selection of tolerances of dimensions, shape and location of surfaces, requirements of roughness in drawings are given. The manual is intended for students, young specialists and engineers of engineering specialties, it can be useful for students of technical schools and technical schools.