Safe and Non-toxic: It is made of food-grade silicone, BPA-free, PVC-free, lead-free and phthalate-free. Its adjustable cord and detachable buckle make it safe for most children to use. Adjustable Split Buckle: Each of our rainbow chew necklaces is equipped with a split safety buckle to ensure the safety of your loved one. Although the use of these necklaces should be used under adult supervision, safety clasps have been added to provide additional protection. The length of the pendant necklace can be adjusted as needed. Helps Reduce Stress and Anxiety: This chewing necklace is suitable for those with oral sensory needs to promote calm, soothing and focus. Reduce chewing on pencils, hands, clothes, hair, etc. Sensory Stimulation: Design a textured back to soothe and calm children with autism, hyperactivity, PDD, ASD. Stop biting pencils, chewing clothes and sucking thumbs. Reduce the risk of dental problems immediately!