Four Modes give kids more freedom while keeping them safe. The vest and wristband are made of breathable cotton that provides 360 circular ventilation that ensures comfortable and safe use for both parents and children. Snap closure Strap with Double Hook and Adjustable Buckle --- The size of the wrist strap can be adjusted according to your needs. Double hook and loop strap closure prevents baby from pulling out. The shoulder strap and safety buckle are adjustable and can be resized as your baby grows, making it more comfortable for your baby. Safety Lock and 360 Degree Rotation --- The key on the parent's bracelet can lock the child's bracelet to prevent the baby from loosening and make the trip safer. The wire adopts elastic steel wire design, which is of good quality, more durable and easy to stretch. The 360-degree stainless steel rotating buckle of the waist link can rotate freely with the needs of the child without entanglement.