Age Range:> 6 years old Description: 1. Material: alloy 2. Weight: about 15 grams 3.Description: Each set of decompression chains is made up of 18 small parts. 4. Packing: plastic bag 5. Function: this product can help users to quit smoking, ADHD, obsessive-compulsive disorder, anxiety, post-traumatic stress disorder, meditation and boredom, and has a calming effect.