Eagle X-Sync 2 Oval Direct Mount Chainrings Compatible with 11s and 12s The longer, positive-rake tooth shape has been designed to work perfectly with the new Eagle� chain to increase chain retention and overall pedaling efficiency, while decreasing friction, noise and wear X-SYNC� 2 chainring design increases chain retention, wear life, and reduces friction and noise now in an oval shape for improved pedal efficiency Designed to be used with Eagle� chain Direct Mount 36T Black 12sp Narrow/Wide 3mmUPC/EAN/GTIN: 710845804700