Perfect Jaw Shape: Say goodbye to double chin and slack facial muscles. Safe and high quality materials: This Exercise Jawline is made of food grade silicone, which is BPA free, non-toxic, elastic and not easily deformed. You can exercise with confidence. 2 Pieces of Jaw Exerciser: Dimensions: 2.8 x 2 x 1.7 cm, the resistance is about 45 pounds. This jaw ball is suitable for everyone, perfect for your back molars for best results. Easy to use: bite down firmly on your molars for 10 seconds, feel the muscle exerting force, then relax- YOU. Repeat 3-5 times per minute (please do not chew quickly), you can exercise every day according to your own situation. Easy to carry: The jaw trainer can be taken with you and used on the go, at the gym, at work and anywhere. Color: Grey Shipping Quantity: 2 Due to manual measurement, there may be 3-5mm error Note: The data is manual measurement, please allow error 1-48cm, due to differences between light and screen, there will be a certain color difference, the specific received in kind prevail.