Sram:

SRAM X-SYNC 1X chain rings provide the highest level of performance and durability. The SRAM X-SYNC tall square teeth edges engage the chain earlier than traditional triangle shaped teeth. The sharp and narrow tooth profile, as well as rounded chamfer edges, help manage a deflected chain. To provide the best possible performance in muddy conditions, the X-SYNC chain rings have been designed with mud-clearing recesses for the inner chain links and rollers. Engineered in Germany, X-SYNC rings are an integral part of the SRAM 1X drivetrain.