This refill pack contains a single, clear Comfort Size #1 mouthpiece that provides a slight +2mm jaw adjustment. Size #1 is recommended for those with an overbite or a normal bite with light to moderate snoring. If you're new to ZQuiet, consider starting with the 2-Size Starter Pack to determine which size resolves your snoring. Once you've identified your ideal size, order either Size #1 or Size #2 separately. ZQuiet's mouthpiece is soft, low-profile, and flexible, providing a lightweight, comfortable feel. It's less bulky and intrusive than similar products with a hard plastic shell. ZQuiet’s living hinge technology with an open front design lets you open and close your mouth naturally and even allows you to talk or take a sip of water. Minor side effects, such as drooling or jaw discomfort, are normal and tend to fade with consistent use. (See tips on adjustment in the content below.) For proper hygiene and optimal performance, replace your ZQuiet mouthpiece every 4-6 months.