HEAD - TwinHead™ w/ air release button & x-long hose

Races are hardened to R-62 and polished to a mirror finish with ABEC 3 certification for tolerance and noise

Cons: Not much this is a great all round rotor

The front flap is perfect for spares and tools

Shimano Dyna-Sys 11 Speed Jockey Wheel Set - High Grade - Deore XT Level Virtual Parent HEAD - TwinHead™ w/ airShimano make 3 different quality levels of jockey wheels to suit their 11 speed derailleurs. They are all cross compatible, so you can "upgrade" your SLX or XT 11 speed derailleur by adding Premium Grade XTR wheels if you like! At the top of the tree is the Premium Grade XTR Jockey Wheels. These are the same as the orignal jockey wheels found on 9000 or 9020 series derailleurs. They feature exceptionally well sealed cartridge bearings, a mud shedding