This mouthguard from Safejawz Intro series consists of 2 layers for optimal cushioning. Fluid-Fit is used so that the protector can be fully adapted to your teeth. This keeps the mouthguard perfectly in position during exercise. Safejawz's Jaw Secure technology ensures that your lower teeth are protected as well, even though it's a single mouthguard. Due to the unique shape of the base, you can let your teeth into the mouthguard. This ensures that both your teeth and your jaw are perfectly protected. The mouthguard can be adjusted up to three times if you are not completely satisfied with the fit.