•SmartStart bikes are an incredible feat of kid-size engineering. From top to bottom, they’re designed to outsmart physics and help kids in motion stay in motion. •Single-speed drivetrain is simple to use and easy to maintain. •Includes both rear coaster brake and front caliper brake; easing the transition to a bigger, hand-brake-only bike when they’re ready. •Features removable training wheels and handlebar number plate. •16-inch wheels fit riders 38 to 48 inches tall. Tool-free adjustable saddle allows the bike to grow with your child.