If you want your pulley wheels to spin endlessly then the Gen 1 Pulley Sets will fit the bill, being durable and smooth running, ensuring the longevity of your drivetrain while maximising your power output.
Compatible with 10 and 11 speed derailleurs from a variety of models of SRAM, Shimano and Campagnolo derailleurs, these aluminium pulley wheels come with a choice of high quality but affordable hybrid ceramic bearings, or full ceramic for the lowest possible friction and the fastest speed with the least effort.
The hybrid ceramic bearings use the same type of bearings as the Kogel's bottom brackets, which will provide a balance of excellent durability with low friction in all conditions, but if the lowest possible drag is what you are after, the full ceramic option is for you.