The SHIMANO DEORE XT FC-M8100-1 crank features an entirely new construction using direct mount chainrings special gear tooth profile for improved chain retention and a 172mm Q-factor. Special MTB gear teeth profile improves chain engagement and retention Hollow forged crank maximizes power transfer while limiting weight Superior chain retention Rigid and lightweight design for aggressive trail riding Q-factor 172 mm Chainline 52 mm Weight 608 g 28T 622 g 30T 620 g 32T 633 g 34T 651 g 36T