The Gel Nano Mouthguard is fully equipped with a gel-fit liner. The gel liner has been designed to take a self-fit custom impression of your teeth upon purchase to ensure security and comfort throughout the guards lifespan. With your teeth nestled in the vertical wall frame, the jaw line is secured limiting injury from side impact. Take the personalization of your Shock Doctor product even further by choosing from an array of offered colors. Features High impact shock absorption. Increased athletic performance. Ultimate custom fit.