GMC Denali XL Road Bike (22.5"/57.5cm Frame) 21-speed road bike features a 7005 aluminum frame and durable steel fork Outfitted with a full array of alloy components including brakes, crankset, handlebar, stem, and wheels Shimano Revo Twist Shifters boast precise movement and light action Sturdy triple chainring alloy crank, and trusty Shimano TZ30 derailleurs round out the drivetrain Light and strong alloy wheelset features V-profile rims