100% Food Grade Silicone: Designed with 100% BPA-free food grade silicone, softer and more elastic, provides better biting experience, non-toxic food grade silicone, PVC, phthalates, lead and cadmium. Massage & Stimulate Gums: The teethers have two textures of stripes and particles, they can effectively contact the gum area on both sides of the baby’s milk teeth and massage to promote teeth growth. And effectively relieve the problem of itchy gums when teething. For 0-6 months, 6-12 months, 12-24 months Sensory exploration development: pliers, wrench, double wrench and hammer, different shapes of teethers help babies explore the world by using their senses to learn about texture and develop mouth muscles. Promotes baby’s sensory development. Perfect size - Easy for baby to grasp: Fully studied baby’s palm size and baby’s grip strength, curved design and 1.14 weight oz to 1.83 oz are easier for baby to hold. Easy to clean: Liquid silicone has good high temperature resistance.