Lightweight and sturdy: The aluminum frame of the Wahoo is robust and durable, yet light enough to be effortlessly controlled by children.;The closed dropouts with Treks ThruSkew axle prevent the wheels from accidentally falling out.;An uncomplicated 1x8 drive system simplifies gear shifting, allowing your child to focus on the fun of riding.;Trek's children's bikes are an investment in quality - they are built with the same care as the adult Trek bikes.