Professional Silicone Jawline Exercise Ball Fitness Face Masseter Muscle Exerciser SBlue Condition: Item Type: Jawline Exercise Ball Material: Silicone Size: As Shown in the Pictures Applicable People: The face is too fat, the face is not contoured, and the facial muscles are sore Operating Instructions: Step 1: Put the jaw exerciser into boiling water for 20-24 seconds. Step 2: Cool down, and then put the jaw exerciser into your mouth. Step 3: Bite the center of the bite strip until the jaw trainer is in place. Step 4: Release the bite and bite again, a total of 15 repetitions. Step 5: Rest for 1 minute. Step 6: Repeat this cycle 3-4 times a day, and slowly increase the weight as you feel strong.