Rubber sole Arch Support: The insole has an arch support design to help the baby form the arch faster. Good Material: Fiber upper, soft and breathable. Anti-collision: collision avoidance toe cap adds extra barrier to protect baby’s feet from injuries. Flexible:1/3 correct bending helps baby’s feet flex correctly, and ensures naturally movement. Easy On and Off: baby shoes features kid-friendly hook-and-loop closures allow for secure fit and custom adjustability.