The derailleur for 33Z0105 type scraper is also called chain splitter and fork. The derailleur is a structural part.
        When installing the derailleur, the shift fork is inserted into the groove of the sprocket teeth, so that the chain of the scraper chain and the sprocket can be smoothly engaged and separated. The function of the derailleur is: when the sprocket shaft group is disengaged from the meshed ring chain, the chain ring is prevented from being caught in the groove of the sprocket and cannot be disconnected at the normal separation point.