Food grade EVA, BPA free, non-toxic, environmental friendly It is slim and custom fit to make you talk, breath and drink without removing the guard Easy to fit and molds to teeth and gums, providing a comfortable fit for extended use Scientific design provides maximum comfort and convenience It can be re- built about 20 times Suitable for all contact sports such as basketball, lacrosse, hockey, MMA, boxing,especially Hockey and Football Specification: Material:Food Grade EVA Size: One size, approx. 7.6 x 3 cm/ 3x 1.2 inch Thickness: 1.6mm How to Use: Step 1: Please put it in 54 degree hot water about 25 seconds until it becomes soft Step 2: Take out the gum from the hot water by sticks/forks and then Put on the guard to take shape Step 3: To memorize your mold of teeth, bite it 10~15 seconds Step 4: Put the shaped gum to cold water to make it solid It can be re-shaped if it doesn't fit well at the first time Package Includes: 1 Piece Mouth Guard Note: Please caution the hot water when you soften it especially your kids Please keep it clean and disinfect it after using it