SHIMANO 110BCD R9200 R8100 2X Completely closed Road bike Gravel bike

Model  48-35T or 50-34T or 52-36T or 53-39T or 54-40T or 56-42T Colour Black Made from 7075-T651 Aluminum Alloy Surface coating Anodizing Made with CNC milling Chainring shape Round Compatible cranksets Shimano FC-R8100 - ULTEGRShimano FC-R9200 - Dura-Ace Weight, grams  161 (48-35T), 173 (50-34T), 193 (52-36T), 207 (53-39T), 259 (56-42T) Chain compatibility Standard 11/12 speed  Support paying an extra $10 to customize the same silver color  Bicycle shop or dealer contact customer service              PASS QUEST 2X CHAINRING The Fully enclosed transmission Chainrings2X ismilled from a whole aluminum plate by CNc, which ismilled thin and chamfered to ensure strength whilereducing the weight of the gearbox. The gearboxsolves the problem of chain drop and chain noisefrom the root by optimizing the internal structureand transmission system. (BCD:THE CENTER HOLE OF THE DISC NAILFORMS THE DIAMETER OF THE CIRCLE) FC5800/