The Anti-Snoring Device By SmartGuard is a safe and effective one size fits-all custom molded Snore Stopping nightguard that is meant to be worn while you sleep. SmartGuard s Anti-Snore Mouth Guard works by advancing your lower jaw while you sleep keeping your airway open and preventing snoring. SmartGuard s design is uniquely comfortable and effective allowing you to freely open and close your mouth while wearing the Anti-Snore Guard. SmartGuard s Anti-Snore Appliance is made up of two separate trays that mold to the upper and lower teeth to form a custom fit. SmartGuard s advancement bars connect the upper and lower Anti-Snore Guard into a single comfortable design that effectively keeps the correct jaw position without limiting your jaw s natural range of motion.