describe: How to install your jaw exerciser? 1. To fit, first practice placing the jaw exerciser, Then feel the width of your mouth should be open. 2. Put the mandibular exerciser with bite bars into boiling water for 20-24 seconds. 3. Remove the jaw exerciser from the boiling water, shake off the excess water, but don't wait too long for it to cool down. 4. Put your thumb into the hole, place and adjust the mandibular exerciser to bite the bite bar. 5. Bite and hold for 15 seconds to customize the mouthpiece according to your own mouth contour. 6. Take the chin exerciser out of your mouth and cool your imprint under cold water for a few seconds to permanently fix the imprint. feature: Strengthen your jaw line-the well-defined jaw line looks younger and better With revolutionary patented technology, quickly slim down, tighten and tighten your face and neck Convenient, hands-free exercise-carry it with you, use it anytime, anywhere Reduce cravings-chewing has been shown to reduce cravings, leading to more weight loss It is a facial exercise product that helps to strengthen and regulate facial muscles. Get a more three-dimensional face and make your face look completely new. It only takes 10 minutes a day to start seeing the difference. With enough training, rest and nutrition, your facial muscles will grow like other muscles describe 100% brand new, high quality Material: Silicone Size: One size Color: black, blue, red, green, purple Package Included: 1 x jaw exercise 1 x string 1 x box 1 x instruction