At 18 in this is the largest wheel size in the range and it fits riders 47.2 in to 59.1 in tall or roughly ages 4 to 8. The saddle runs 23.5 in to 27 in and matches a 23-in to 26-in inseam so a taller child can stop flat-footed. Detachable training wheels are still included for the transition and unbolt once they are no longer wanted. The metal frame and seat carry up to 145 lb Crack-resistant tires handle bike path asphalt and packed gravel shoulders and a kickstand parks the 25-lb bike at any rack.