Derailleur Arm – the arm which extends from your rear derailleur, with pulleys to feed the chain by way of. The derailleur arm is spring-loaded to get rid of slack from the chain when working with more compact gears. Very easy to ASSEMBLE: Notes: The kit desires simple hardware capabilities https://bikeengineoilchangekm26801.pointblog.net/facts-about-chinese-made-dirt-bike-engines-revealed-79599389