C shape design- Ergonomic to use, highly anastomosis with your mouth. Helps give you an unobstructed view of the oral cavity. High-quality materials- 11.8*8.5*1.7cm(Medium Size),10 pieces to a set, made of medical quality polycarbonate. The edges are smoothed and these are comfortable to wear. Protect oral health- They're often used with home teeth-whitening procedures to open the mouth and keep the whitening agent away from lips and gums. Methods of playing the games - Put one of these mouth openers and try to say a challenge phrase while you can't close your lips,make your partner understand what you're trying to say, the fun begin. Recyclable- Features a sturdy, completely recyclable to save you money on the long-term. And please contact us if you have any questions about the product, we will give you a satisfactory solution. Specification: - Color: Transparent- Shape: C-shape- Medium Size: 11.8*8.5*1.7cm Functionality: - C-shape helps give you an unobstructed view of the oral cavit - Be comfortable to wear for most people over 13 to play the mouth opener games - So whether for fun, for serious use, or for both, these are the "mouth openers" you need Package Include: 10 * C-Shape Mouth Opener