Features • Free food-grade silicone is used to make the jaw sharpener. The same material as a baby pacifier is used in our double chin reduction. Silicone that is non-toxic and free of chemical additives and byproducts, making it safe to chew on. • Men's and Women's Safety Jaw Exercisers: Please use with confidence because it is made of food-grade silicone that is BPA-free and non-toxic. Before you use it, boil it for 20 seconds. • You may use it at any time. It's a breeze to transport. • Using the fitness balls, you may eliminate fat deposits around your jaws and neck, as well as tone and tighten your face, neck, and jawline.