Materials: bio glass with negative ion Package included: 1 piece pendant Main function: 1.Enhance blood circulation and metabolism 2.Stabilize the oxygen supply 3.Promote cell activity and strengthen human immunity Health benefit in long term: Quantum pendant produces scalar energy that helps enhance our body's bio field and restore energy that has become weak in our body. By restoring the energy balance in our body, it will keep us healthy Note: 1. Please allow 1-3mm difference due to manual measurement 2. Due to the different display and different light, the picture may have a slight difference with the actual color of the item Thanks for your understanding