Made of aluminum alloy material,workmanship, solid and firm, very durable. This product is used for rear derailleur extension, apply mountain freewheel 40T/42T/46T/50T or 32T/36T Road flywheel. Expand the flywheel speed change more smoothly. Adding this product in the original bicycle eral dial hook the converter, you can easily solve the troubles you encounter. Great accessory for cycling enthusiasts.
Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!