20" A1 Premium Aluminum ATB frame with low standover height for care-free starts and stops with room for full-sized water bottle 40mm-travel suspension fork with lightweight alloy lowers and pre-load adjust takes the edge off bumps for more control Lightweight 32-spoke alloy rims are durable and provide a stable platform for learning Specialized Roller tires provide a knobby grip for dirt, but roll easily on pavement Forged alloy crank arms give big kids more power, and a chainguide keeps pant legs clean on the way to school Adjustable alloy V-brake is light and reliable - perfect for kids' transition to adult bikes