The Non-Directional design allows maximum compatibility. The X-Bridge system on the outer plate is configured with precisely articulated angles for quicker and smoother gear shifting, and quieter riding. This chain is compatible with 12x Campagnolo, Shimano and Sram MTB. They are not compatible with Sram road groups, this is due to a difference in pin length.   Features Includes non-reusable 12x Missing Link. Double X Durability. Non-directional. Successor to BX12N0126. Specification Weight: 268g. 126 links.