Silicone Necklace Material--100% silicone, flexible, nontoxic and non-stick. Size can suitable for adult and children Health protection silicone necklace1.Material--100% silicone, flexible, nontoxic and non-stick.2.Use -- muscle power up, improve blood circulation, sooth tension ,enhance upgrade the power of concentration, very helpful for students, researchers, businessmen and athlete.3.Size can ...