This new derailleur not only answers the Eagle(TM) drivetrain&&';;s need for greater capacity, but is also the next evolution of our proven, 1x-specific X-HORIZON(TM) design. The larger, 14-tooth X-SYNC(TM) lower pulley, allows 10- to 52-tooth cassette capacity in this compact design, and also adds to Eagle&&';;s overall smooth-pedaling feel. Our new, Type-3 ROLLER BEARING CLUTCH(TM) features a smoother torque curve for a quieter, more consistent operation and feel. CAGE LOCK(TM) has been moved back and out of the way, protecting it from trail debris. A redesigned, robust mounting system further improves the Eagle(TM) derailleur&&';;s performance and overall durability. Completely redesigned rear derailleur incorporating our proven X-HORIZON(TM) design and new Type-3 ROLLER BEARING CLUTCH(TM) technology Re-engineered mounting system and repositioned CAGE LOCK(TM) add robustness Eagle(TM) pulley technology provides greater efficiency, crisper shifting and quieter operation Carbon cage and lightweight hardware make it light and tough SPECIFICATIONS SPEEDS - 12 MATERIAL - Forged aluminum and carbon fiber OUTER CAGE - Carbon fiber INNER CAGE - Forged aluminum SPRING - Titanium BEARINGS - Stainless CAGE SIZES - Eagle(TM) MOUNT OPTIONS - New improved B-Bolt attachment improves RD durability and consistency. PULLEYS - Eagle(TM) chain compatible TECHNOLOGY HIGHLIGHT(S)X-HORIZON(TM), X-ACTUATION(TM), X-SYNC(TM), ROLLER BEARING CLUTCH(TM), CAGE LOCK(TM) B KNUCKLE All new B-Bolt attachment method reduces noise and improves durability OTHER Type 3 ROLLER BEARING CLUTCH(TM)