For 26", 27.5"(650B) & 700c wheelsA wrap-around seat structure creates a virtual cocoon of protection and features an updated shoulder harness with a multiple height adjustment system. An innovative suspension system cushions bumps and jolts and the integrated roll bar provides extra head protection and doubles as a carrying handle. Adjustable footrests and straps keep small feet away from spinning wheels. Child seat complies with stringent European, CPSIA and Proposition 65 safety standards.The included heavy-duty rack features an innovative BabySeat™ II attachment that requires no tools to attach and remove seat from rack. Once the seat is removed, the exposed QuickTrack™ system is compatible with all Topeak MTX TrunkBags and MTX Rear Baskets.