The Y/1 Mountain 20" has been designed for kids in the prime bike riding age of 5 to 8 years old. In addition to a smooth shifting 1X drivetrain, carefully thought-out geometry, and age-appropriate componentry, the bike features grown-up technology like hydraulic disc brakes, air suspension fork, and specifically tuned return springs. This is not a kid's toy - this is a legit mountain bike designed for riders 5 to 8 years of age. It is perfect for enthusiasts from 5 - 8 and parents who want their youngsters to have the same access to adventure they enjoy themselves.