Sram SX Eagle Aluminum Rear Derailleur 12 SpeedThe Sram SX Eagle Aluminum Rear Derailleur 12 Speed features the proven SRAM 1x-specific X-HORIZON design and easily facilitates 11-50t and 10-50t cassette capacity, providing quiet, consistent performance and durability. The X-SYNC pulley technology provides greater efficiency, crisper shifting and quieter operation. The Cage Lock offers discovery-level riders easy trail side wheel removal. Long cage length with a largest cog of 50t. The chain wrap capacity is 40 teeth. Compatible with SRAM X-Actuation shifters. Available in Black.710845865206