RDX's pulleys are intentionally designed with an integral amount of "float," or lateral movement. This movement allows the pulley to settle into an optimum position under each cassette cog. The result is faster, smoother shifts and a quieter drivetrain. In our experience, these are the best-shifting after market pulleys available, past or present.
Each RDX's pulley wheel is equipped with a high quality hybrid ceramic bearing for low friction shifting. The advantages of using a ceramic bearing in the rear derailleur's pulleys are the most dramatic of any other bicycle bearing system. This is due to the high speed at which the pulleys spin - often as high as 600 RPM. With ceramic bearing speed increases up to 4%. This means over 1km a rider can gain 20-40 meters!
Each pulley is machined from light and strong 7075 aluminum and anodized, with laser cut logos.