Highly Adjustable for Every Kids - The stretchable spring wire is coated with wear-resistant PU coating, up to 1.5 m(4.9ft). The size of the wrists at both ends can also be freely adjusted to a comfortable size for children under 10 years old. Baby Friendly Material - Made of soft organic cotton, breathable and comfortable for children. Even if it is worn for several hours, there will be no uncomfortable scratches or sweating, and it can be used all year round. Keep Your Baby within Reach - The 1.5m-long spring rope built in 49pcs steel wires is connected with the 360 degrees swivel head, so that your children have more free space to play outdoors in your sight without tripping over. Safety Night Reflective Strip - Designed with reflective strips to warn drivers to avoid children at night, and you can easily see your children at night in crowded streets, shopping malls or other places with low light. Maximum Safety for Your Little Ones - Our anti-lost toddler reins upgrade with key lock - only be opened by the end of the parents' wrist, and the widened metal head makes it difficult to be cut off.