Due to wrong material choice, the derailleur cage will loosen with time and some day break.
There has been a recall for WiFLi derailleurs in 2013, but also the short and XX derailleurs before 2016 are affected. SRAM changed the bolt on the cage to steel from titanium that year.
If you own one of these derailleurs I strongly recommend to check it for play and send damaged derailleurs to SRAM. Mine was replaced.
These derailleurs are a fall hazard.
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