Calculates the stress on the teeth of external and internal spur gears (straight and helical teeth) and conical (straight and spiral teeth) based on the chosen material, the stress conditions (Power, Rotation speed) and the dimensions of the gears (Module, Number of teeth, width of teeth). Among the available materials, not all of them can be selected, as this is a free trial version of the most complete application in a paid (Pro) version.