
Incorrect thread pitch. You can't thread these shafts onto standard Ender 3 nuts. Worse, the nut holes don't match the factory ENDER 3 holes. In my opinion, these are standard shafts and nuts, or else this company has a very poor quality control department. Don't buy them anyway, most 3D printers are METRIC with thread and nut spacing sizes set to wrong specs, that tells you enough

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