When you overhaul the gearbox reduction system, you will need to unscrew the locknut that secures the inner bearing, after which you will not be able to reuse it, as the locknut is disposable.
Don't forget to order this locking nut when you need to replace the bearings, it would be a shame if your project was delayed because of this.
Don't worry about the fit, this nut matches the original in every way.
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