Enduro Bearings Derailleur Pulleys 12T-5mm XTR x 12spd w/XD-15 Black (BKCJ-0361) WTB which is typically the primary

which is typically the primary cause for premature bottom bracket bearing failure

Glide over rocks and obstacles with the Whippersnapper™ system

derailleur/shifter of choice without a change in chain retention quality

keeping grip reliable whether the trail is loose and dry or straight-up saturated

Enduro Bearings Derailleur Pulleys 12T-5mm XTR x 12spd w/XD-15 Black (BKCJ-0361) WTB which is typically the primaryBKCJ 0361 11 tooth, XD 15 Ceramic Hybrid Bearing, Machined Delrin Derailleur Pulleys for 12 speed Shimano XTR and XT Derailleurs (5mm bolt hole) The ultimate upgrade pulley. Guaranteed to last forever against corrosion Precision machined Delrin Derailleur pulleys featuring XD 15 Ceramic Hybrid, radial bearings for enhanced shifting performance and longevity. Designed and manufactured for performance, these pulleys feature CN (tight clearance) bearings