Take the guess work out of determining what model STRIDER Bike is right for your child. Both the ST (STRIDER No-Pedal Balance Bike ST-1, 2, 3, & 4) and the SS (STRIDER Super 16 No-Pedal Balance Bikes) have very different features that are made specificaly for children in the age range suggested for those bikes. Please see the chart below to find the right bike for you.