absoluteBLACK Premium Shimano 110/4 bcd compatible ROUND chainrings are designed for new and old type of Shimano cranks like Dura-Ace 9100, 9000, Ultegra 8000, 6800 & 105 R7000 and more. These are finest round aftermarket chainrings in terms of shifting, stiffness and manufacturing quality. 10/11/12spd compatible.Size (Weight):34T (30g)36T (38g)38T (43g)39T (45g)50T (114g)52T (129g)53T (136g)Compatibility: In short EVERY Shimano 4 bolt crank. Shimano Dura-Ace 9100, R9120, R9150 & R9170 Di2 & all 9000 series, Ultegra 8000, R8020, R8050 & 8070 Di2 & 6800, 105- R7000, R7020, R7070, 5800, 4700. Di2 compatible. 10 / 11 / 12spd compatible. Use bolt covers for best appearance.Material: cnc machined 7075 Txxx Aluminum. Long-lasting construction. Type II anodizingMounting: 110BCD x 4Bolts: For Outer chainring use Absolute Black "Long bolts" or our Bolt Covers. If you're changing the the inner chainring only then use your original bolts.