Carbon-Ti chainrings do not include the catch pins that are commonly found on most other chainrings. The reason for this is because Carbon-Ti chainrings are often mounted on various cranksets and the catch pin would only function properly if it was perfectly sized to the specific crank arm. For example, if the pin was too long, it would prevent the chainring from being installed on the crankset. Likewise, if it was too short, the catch pin wouldn’t serve it’s intended purpose and even worse, the chain could get stuck behind the catch pin. So the lack of a catch pin allows for a much broader range of compatibility. It also allows the Carbon-Ti chainrings to be used on a SRAM hidden-bolt crankset.
Carbon-Ti X-CarboRing EVO 110×5 Road Chainrings