Chasing PRs and race podium spots take special equipment.Removing every bit of mechanical drag is important, both mentally andphysically, if you want to go as fast as you can. That explains why the proshave their mechanics swap out the standard bearings and parts for upgradedcomponents with ceramic bearings to help provide an edge over the competition.Now you too can get this advantage by hopping up your rear derailleur withCeramicSpeed's 11 Speed Aluminum Pulley Wheels for Shimano, SRAM, and Campagnolorear derailleurs. Derailleur pulley wheels are some of the fastest rotatingparts on your bike and unlike components built to go faster in the wind whereyou have to be traveling at a fast rate of speed to reap the benefits,drivetrain friction occurs at every speed. The pulley wheels feature the standard CeramicSpeed Bearingsthat many pro teams count on the eke out a few more watts that's often thedifference between first and second. CeramicSpeed designs these pulley wheelsto provide the ideal chainline and perform precise shifts and smooth pedaling.In addition to delivering lower friction, CeramicSpeed claims that the durable,22-gram aluminum wheels last 3-5 times longer than stock pulley wheels. Eachkit includes 2 pulley wheels, spacers, oil for maintenance, and a stickersheet.