Replacement Shimano rear derailleur on the M1, F1 model bicycles. The part number for this Bintelli E-Bike part is BB-31.
This is a genuine Bintelli Bicycle part. If you have any questions regarding whether this part will fit on your electric bicycle, please either contact your local dealer, or you may email Support@Bintelli.com or call us at (866) 542-8677. We look forward to assisting you.