Product Description Shimano sprocket Dura-Ace CS-R9100 - 12 tooth for 12-25 and 12-28 This Shimano sprocket (12 tooth) is compatible with Dura-Ace CS-R9100 11-speed cassettes in 12-25 and 12-28 gradations. It is made of steel and comes with a built-in spacer. It can also be used for Dura-Ace CS-9000, as a replacement for the original sprocket, which is now out of stock. Technical Information:Gearing:11Gradation:12-25, 12-28Type:w/ integrated spacerCompatibility:CS-R9100CS-9000Manufacturer Number:12 tooth:Y-1VT12100 Note:13 and 17 tooth are identical sprockets for CS-9000 12-25 / 12-28. 14, 15 and 16 teeth are identical to sprockets for CS-9000 11-23 / 11-25 / 11-28.Contents:1 x Shimano Dura-Ace CS-R9100 sprocket Manufacturer: Shimano Europe B.V. High Tech Campus 92 5656 AG Eindhoven Netherlands info@shimano-eu.com