These Praxis compact 110BCD road chainring sets are engineered for the highest performance shifts in all conditions. LevaTime® performance and proprietary forging process give the fastest shifts and longest lifetime of any chainring on the planet. Compatible with Shimano (Except the new Ultra 6800/DA9000 cranks with their new custom asymmetrical BCD). Sram and Campagnolo (Except on Campagnolo cranks with their proprietary Campagnolo BCD/Design, you would need to use third party cranks). These Buzz Rings also work with eTap and the Sram Yaw front derailleur.