... rotation, shaking, beating, finger-pressing, rolling, etc, it most effects on head and eyes of human being. 3. Most effective to ... blue color, every time you press the key, blue color displaying on LCD video screen for 15 seconds.Product Functions: 1. Head and ... , writers, office staff and etc who often use computers and watch TV suffering headache and near-sightednessApproval : CE, RoHSFOB: Shenzhen , ...