The Hayabusa Combat mouthguard has a latex-free silicone gel that provides comfortable impact protection. Its dual density works together to provide a secure fit with full coverage. Simply snap it closed and bite in to protect your mouth, teeth and gums. Fitting Instructions: Boil water Pour hot water into the cup immerse the mouthguard for 30-90 seconds remove with a cutlery and allow to cool until the temperature is acceptable adjust to the correct position in front of a mirror bite firmly, applying even pressure with fingers and tongue hold for 30 seconds to make sure it conforms to your teeth carefully remove the mouthguard hold under cold running water to cool completely test the fit to make sure it fits properly If the mouthguard does not fit properly, repeat steps 1-10.