It is summarized in: A.- Calculate the parts of the straight gears in metric version. B.- Contains the essential theory to perform the geometric calculation of the straight gears. C.- Carry out the calculation for the milling of the straight gears by loading the data of their hole plates, in addition it is calculated in the form of direct or indirect division. D.- Soon it will be possible to calculate with differential division. F.- It comes in English and Spanish and is being translated into Portuguese. G.- It has a free version. "CalcGear", Try it.