SRAM CHAIN PC XX1 EAGLE HOLLOWPIN 126 LINKS POWERLOCK 12 SPEED BLACK 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. & it’s also the biggest contributor to the Eagle™ drivetrain’s ultra-smooth precise durable & quiet performance. The Eagle™ chain’s links have a smooth radius with no sharp edges or chamfers which yield a significant reduction in noise friction & wear on chainrings & cassette cogs. This design also allows for a flatter plate which means more consistent chain riveting & greater overall strength. HARD CHROME™ technology extends the chain’s optimal performance life & a Titanium Nitride coating on the Gold & Black models decreases corrosion & further reduces friction.