The name of these pulleys came from the fact that Instagram videos are limited to 15 seconds. There is no way to show how well they spin in 15 seconds. They just keep on going and going!
The bearings in these 11 tooth pulley wheels are full zirconia ceramic and require no lubrication.
Compatible with 11 speed Shimano, Sram and Campagnolo derailleurs. Although the quality of these bearings is good enough for us to back them up with our usual warranty and durable enough to resist daily road use, it does not hold up to frequent mud baths. Sorry mountain bikers, cross and gravel racers!