<ul><li>The Shimano Dura Ace FC-R9200 12 speed chainrings are the perfect replacement for worn or damaged chainrings<li>HOLLOWGLIDE, hollow outer chainring technology, giving vast improvements in rigidity and increased weight savings, whilst also removing outer chainring flex, hugely improving shift performance making it precise even under high load<li>The teeth have been developed to work only in conjunction with 12-speed chains for improved contact providing more efficiency and improved power transfer<li>Genuine Shimano replacement chainrings for the FC-R9200 & FC-R9200-P cranksets available in 54T, 52T, 50T, 46T (Outer ring), 40T, 36T, 34T (Inner ring) <li>Shimano part numbers: 54T-NJ - Y0MZ98030, matches 40T-NJ - Y0MZ40000, 52T-NH - Y0MZ98020, matches 36T-NH - Y0MZ36000, 50T-NK - Y0MZ98010, matches 34T - Y0MZ34000, 46T-NH - Y0MZ98110, matches 36T-NH - Y0MZ36000<li>Compatible chain Shimano HG 12-speed</ul>