This new NX Eagle™ derailleur features the proven SRAM 1x-specific X-horizon™ design. The larger, 14-tooth X-SYNC™ lower pulley easily facilitates 11 to 50- & 10- to 50-tooth cassette capacity, & adds to NX Eagle's overall smooth-pedaling feel. The Type-3 roller bearing clutch™ provides quiet, consistent performance & durability. Key Features Eagle™ technology provides an expanded, optimum, gear range making you fast on the flats, giving you control on the climbs & unleashing your speed on the descents. Completely new rear derailleur incorporating our proven X-horizon™ design & new Type-3 roller bearing clutch™ technology. Eagle™ ecosystem-engineered mounting system & cage lock™ positioning add robustness. Eagle™ pulley technology provides greater efficiency, crisper shifting & quieter operation. Eagle™ is a complete drivetrain system that was developed to be an integrated high-performance ecosystem. The engineering & testing that went into the development provide for maximum performance, safety, & long-term durability to ensure a great consumer ride experience. SRAM guarantee this performance when Eagle™ drivetrains are used as a complete ecosystem. For additional information, please contact your SRAM Sales Contact.