Mouthguard designed to fit any shape of your mouth. Favored by famous UFC fighters such as Wonderray Silva, Carlos Conditt. Dip in hot water to form the teeth shape. How to Use: (1) Prepare boiling hot and cold water. (2) Soak the mouthpiece in warm water for about 30 seconds. (3) Remove the mouthpiece from hot water, place it in your front teeth and use your fingers to push out the mold. (4) Remove it when you finish the forming, and soak it in cold water. (5) Put it on the front teeth again and check it. If the chewing is poorly bad, please try it back at (1). (6) Finally, if the end or top edge is protruding out, you can cut it out with a pair of scissors.