Additional Details ------------------------------ Product description: 5 pairs of thermoforming trays Step 1: Place the tray over the upper teeth without placing the tray in boiling water. Practice with your tongue on the roof of your mouth and touching the inside of the tray. Suck the air from the tray. This contours the guard to the inside surface of the teeth. When finished repeat with the lower tray. Step 2: Bring water to a boil. The bowl should be at least 4" deep to ensure the tray's full immersion. Remove the container from the heat and place one tray in the hot but not boiling water. Leave the tray in water for 5 seconds. Make sure the edges do not fold onto each other. Step 3: Lift the tray vertically from the water using the tab. Carefully and quickly place the tray around the teeth and then immediately perform the procedure outlined in step 1. Step 4: Once you are satisfied with the fit, trim the front tab away from the tray with scissors. Make sure it is flush with the front surface of the tray.