What's gray and polished and fast all over? Shimano® has managed to make these even more rigid than their previous, industry standard 960 model. Talkin' it like they're walkin' it, Shimano® wants you to know these have: • Patent-protected chain ring design means unmatched shifting performance: Market standard front shifting performance (when combined with a Shimano® front derailleur) is taken even further by the precision molding and machining of the composite carbon fiber and titanium middle chainring and greater rigidity of the outer chainring. • Enhanced durability The titanium teeth of the middle chainring along with Ni plated the double anodized chain interface surface of the outer ring combine to a conservative 100% increase in durability over prior generation XTR chainrings. • More precise bearing adjustment The new left hand crank arm mounting system provides a higher integrity solution that creates more precise bottom bracket bearing adjustment, extending the bearing life while keeping rotating resistance to a minimum. • Lighter weight and more versatile Even with all of the additional benefits over prior generations, the new FC-M970 shaves even more weight from the current model thanks to the composite carbon fiber / titanium middle chainring. The 44-32-22 rings also share the same bolt pattern as other popular Shimano® cranksets such as XT® and LX® .