The Shimano XTR M9000 Race 38/28 11 Speed Double Chainset is ideal for those who value lightweight strength and a wider gear range on their cross country bike. These class leading cross country race focused cranks are compatible with XTR 1x or 2x chainrings on its narrow 158mm Q Factor crankarms. The crankarms are made from a carbon aluminium construction with a 3D hollow structure to increase stiffness and minimize weight. The outer chainring is made with a titanium/aluminium composite hollow 3D structure to maximize stiffness whilst keeping weight at a minimum and titanium teeth are used to create a stiff, light weight and hard-wearing chainring. 38/28 with a 48.8mm chain line and a 158mm Q-factor ideally suited for XC Race use in conjunction with 11-40T cassette. Available in silver only with 170 or 175mm length crank arm lengths.