The SHIMANO DURA-ACE RD-R9100-SS Rear Derailleur R9100 11-Speed Short Cage 11S is a high-quality rear derailleur designed specifically for Shimano brand bikes. Made of durable aluminum material, this lightweight derailleur weighs only 0.34lbs and comes in a sleek black color. With 11 speeds and a short cage derailleur cage length, it is compatible with various bike types including road bikes, cruisers, dirt jumpers, and more. This rear derailleur is a reliable and essential component for maintaining optimal gear shifting performance on your bicycle. Made in Japan, this Shimano derailleur meets the highest standards of quality and performance.