The GT Stomper Prime 20 is the mountain bike for the active kid that isn't quite ready for a full size adult mountain bike. GT made this bike to be durable, versatile and ready for the most active kids aged 6-9. Groupset: Shimano Tourney 1x 6-speed Crankset: 110mm length, 30T Cassette: 14-28T Pedal: GT Flat Pedal Shifter: Shimano Revo Twist For Small Hands Suspension: None (Rigid frame) Brake Type: Rim Brake