catena shimano dura ace ultegra shimano 105 cn 6701 10sThe directional chain with inner and outer links specially designed to optimize shifting smoothness. The outer side design was created to minimize the chances of chain suck. The inner side design was created to provide better reliability and smoother shifting even under high loads, offering efficient pedaling along with increased stiffness and quietness. Features Ideal for 10 speed drivetrains Shimano Ultegra Thickness: 5. 88 mm Actual weight: 267 g