SHIMANO ALTUS rear derailleur, 9 - speed. With its MEGA 9 DRIVE TRAIN design, it offers smooth and light - action shifting for an amazing cycling experience.

To use this Shimano Altus 9 - speed rear derailleur, first, make sure it's properly installed on your bike. When shifting gears, just gently press the shifter. It will smoothly move to the desired gear. For maintenance, regularly clean the derailleur with a soft cloth to remove dirt and grime. Also, check the cables for any signs of wear. If you notice any issues with shifting, don't force it. Instead, have it inspected by a professional. Keep it away from extreme heat and moisture to prolong its lifespan.