The mouth guard, a very high protection, thermo-moldable “Nano 3D”, is the finest in the word (approximately 33% thinner than the others) for comfort. They attach themselves at your upper jaw when you open your mouth to breathe. The Nano 3D is the most advanced mouth guard, ultra resistant, dental gel, ultra thin core, super light, to combine the best protection to the greatest comfort for mouth. The core of the mouth guard spreads the impact of the shock. The 3 parts structure is constitute with a larger dental gel area for more comfort and better protection. This technology protects from fracture and dislocation of the jaw, internal lacerations, broken teeth and multiple contusions. When properly mold the teeth are maintained by the gel. It allows high jaw stability. Advices for the thermo molding Put your mouth guard Shock Doctor during 90 seconds in boiled water (Using a large spoon, for example). Pull out, and then dip it, during the 2 seconds, in cold water to harden slightly the upper layer of the gel. Insert your mouth guard in the mouth and grit your teeth during 20 seconds. Then, soak the mouth guard, during 30second, in cold water to harden the gel. Characteristics: MONOCOQUE SHOCK FRAME™: The new ultra thin and hard core is a lightweight structure that, perfectly, absorbs and disperses impact away from the contact point to avoid tooth loss. EXCLUSIVE NANO INNER WALL: A hard core, semi-flexible polymer, improves comfort in wearing. Minimizing contact with the language and the gene caused by that, the technology "INNER WAL" allows breathing easily. TRI-BITE: Aligns and stabilizes the upper and lower jaw by setting perfectly incisors and molars when you close the mouth. The product is not returned nor exchanged if the package is opened.