Geometric designs and strength checks of shaped connections of shafts with hubs. Application is developed in MS Excel, is multi-language and supports Imperial and Metric units and solves the following main tasks: - Design of a connection with parallel side keys. - Design of a connection with Woodruff's keys. - Design of a connection with straight-sided splines. - Design of a connection with involute splines. - Strength check of designed couplings. - The application includes a table of keys and splines according to ISO, SAE, DIN, BS, JIS and CSN. - Support of 2D CAD systems (AutoCAD, AutoCAD LT, IntelliCAD, Ashlar Graphite, TurboCAD). Used standards: ANSI B17.1, ANSI B17.2, ANSI B92.1, ANSI B92.2M, ISO R773, ISO 14, ISO 4156, DIN 6885, DIN 6888, DIN 5464, DIN 5471, DIN 5472, DIN 5480, BS 4235, BS 6, JIS B 1301, CSN 02 2562, CSN 30 1385, CSN 01 4942, CSN 4950. This module is a part of MITCalc - Mechanical and Technical Calculation Package for gear, belt and chain drives, springs, beam, shaft, bolt connection, shaft connection, tolerances and many others.