It might look normal from the outside, but the engineering inside this incredible new chain design that makes possible a gear range previously found only in 2-chainring drivetrains. And it&';s also the biggest contributor to the Eagle(TM) drivetrain&';s ultra-smooth, precise, durable and quiet performance. The Eagle(TM) chain&';s links have a smooth radius, with no sharp edges or chamfers, which yield a significant reduction in noise, friction and wear on chainrings and cassette cogs. This design also allows for a flatter plate, which means more consistent chain riveting and greater overall strength. HARD CHROME(TM) technology extends the chain&';s optimal performance life, and a Titanium Nitride coating on the Gold and Black models decreases corrosion and further reduces friction. Groundbreaking new chain design and technology The Eagle(TM) chain has been completely re-engineered, and is produced with new manufacturing technology All-new Eagle(TM) PowerLockA(R) chain connector with FLOWLINK(TM) technology provides better chain-guiding and increased longevity The XX1 Eagle(TM) chain is the quietest, strongest and most wear-resistant chain in the world Unique features and design also provide significantly improved wear resistance on Eagle(TM) cassettes and rings SPECS TECHNOLOGY HIGHLIGHTS: FLOWLINK(TM), HARD CHROME(TM), POWERLOCKA(R), X-SYNC(TM) COMPATIBLE GEARS: Eagle(TM) 10-50t and 10-52t cassettes CLOSING LINK: Eagle(TM) PowerLockA(R) PVD OUTER PLATE: Nickel + PVD Gold or Black INNER PLATE: Chrome Plated + PVD Gold or Black PIN TREATMENT: Chrome hardened, Hollow Pin(TM) RECOMMENDED GROUP: XX1 Eagle(TM), X01 Eagle(TM) SPEEDS: 12 OTHER AM: Chain length - 126 links, COLORS: Black, Gold COMPATIBILITY: Eagle(TM)