The ACID Pedals C4-ZP Rookie are available in three distinct sizes, to cater for the needs of a range of young riders. The tough plastic cage, durable boron axle, nylon bushing and attached reflectors are common to each version. For the small pedal, the concave tread is ergonomically suited to children aged around 3 to 5. At this age kids will also be held back by a pedal that's too large, which is why the platform is sized appropriately and features shallower pins.