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...Hybrid stepper motor there also exist some special designs one is the disc magnet here rotor designed as a with rare earth magnets this type has advantages such very low inertia and an optimized magnetic flow path no coupling between two stator windings these qualities are essential in applications size power motors classified according to frame sizes which corresponding diameter of body for instance approximately inches likewise mm length may however vary from within same classification general rule available torque output particular will increase increased levels ic driven typically range below watt small up watts larger drive modes...