This type of function is made possible due to the special design of the rolling elements themselves, or the raceways in which they reside, which in the predetermined “free” rotational direction do not oppose the relative motion between the outer and inner rings; on the other hand, as soon as the rotational direction of these elements is inverted, the rolling elements oppose this variation and lock the system. When the system is “locked”, the freewheels work as a friction element, allowing the transmission of drive/breaking torque between the shaft and the housing. 

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