Built for ages 4 to 8, this 18-in bicycle grows with a rider through a quick-release lever that shifts the saddle from 22.5-in to 26-in without tools. Multi-layer tires stack a rubber buffer, cord ply, inner tube, and protective liner to resist punctures on gravel shoulders and cracked sidewalks. Two detachable training wheels come off once balance clicks. A hand brake and coaster brake both bring the bike to a stop, and the sturdy metal frame carries riders up to 132 lb. Non-slip pedals, a bell, reflectors, and a kickstand round out a bike that meets ASTM and CPSIA rules.