Sram: START WITH ONEThe SRAM NX X-HORIZON™ rear derailleur provides the same smooth, reliable shifting action as XX1—from the larger upper pulley offset to the 12-tooth X-SYNC™ pulley wheels. By eliminating unwanted chain movement, X-HORIZON™ shifts faster, puts an end to ghost shifting and reduces shift force and chain slap. And with CAGE LOCK™ technology, wheel removal and installation are easier than ever.FEATURES AND BENEFITS• X-HORIZON™ design that reduces shift force, ghost shifting and chain slap • Most affordable fully featured 1x rear derailleur in the industry• 12-tooth X-SYNC™ pulley wheels• Fully compatible with all SRAM 1x™ drivetrainsSPECIFICATIONSSpeed (RD):  11sCable pull ratio:  X-actuationCage (RD):  LongMax tooth:  42Colour (RD):  BlackPulley bearings material:  SteelCage material (RD):  Steel