Mongoose 29? Mens Impasse Big 29" wheels and an element suspension fork let the Impasse HD roll over tough terrain with ease. The aluminum frame creates a lightweight, responsive ride. 21 speeds with SRAM twist shifters offer a gear range for every kind of terrain while dual disc brakes let you stop instantly in any conditions. Features include: ? Mongoose Aluminum 29? MTB Frame is Lightweight and comfortable to ride; ? 29 inch wheels rolls over rough terrain with ease; ? SRAM twist shifters for easy gear changes; ? 21 speeds with Shimano rear derailleur for all types of riding; ? Front and Rear Disc brakes for confident stopping in all kinds of weather; ? Alloy Crank is light weight and helps the bike to shift gears easily; ? Quick Release Saddle for easy height adjustment, and ? Alloy Rims for Lightweight Durability