20" Mongoose Ledge 2.1 Boys' Mountain Bike Frame: aluminum suspension frame, Fork: suspension fork smoothes bumps and increases control, Gearing (# of speeds): 7 speeds Derailleur: Shimano rear derailleur for precise shifting, Shifter: twist shifters change gears easily Crank: 3-piece crank offers wide gear range, Brakes: linear pull brakes provide great braking power, Wheels/tires: 20" wheels Rims: alloy rims for lightweight durability, Handlebars: steel handlebars, Seat: padded seat, Pedals: standard pedals Assembly required, Dimensions: 51"L x 16.5"W x 35"H, 51.00 x 16.50 x 35.00 Inches