Come and see our amazing products. Children's age and height range: 1-6 years old or Height below 3.5 feet. This child's backpack with Safety Harness Leash, you can hook it at the bottom of the bag, there is a buckle to hang the seat belt. The other side of the seat belt is in your hand, to prevent the loss. The safety leash for this child's backpack is another use, when the parents go out with their baby if both hands have something, there is no way to catch the leash, you can use a safety harness fixed to your own backpack or pants ring. Pls confirm further with us if any query about packing info, inventory status and time schedule.