Part 1 - The Handbook contains materials on the calculation and application of tolerances and fits in machine and instrument engineering, taking into account the Unified System of Tolerances and Fits (USDP), which is mandatory in CMEA member countries. It is supplemented with the data of probabilistic calculations of landings, calculations of dimensional chains operated in areas with cold climate, calculations of dimensional chains, tables of clearances and tensions of the SEB ESDP, the methodology for replacing tolerances and landings of the OST on the ESDP and SEB.