non-toxic, no clicking or squeaking noise, no sharp edges Grip strength increases over time through micro-movements of the hand throughout the during the day, in a meeting/online training, while studying or watching your child play sports, helps to always have a good grip Helps improve grip strength for children sports like baseball, tennis, golf; increase finger strength for hobbies such as rock climbing or music; suitable for men, women, teens, adults, and seniors Easy to use: squeeze, hold, release, and repeat motion with your palm, thumb, and all fingers; insert one finger from each hand and gently pull outward; easy to clean, carry in a bag or pocket to use wherever and whenever you want Satisfaction is guaranteed, we aim to provide our customers with high quality, durable products and exceptional customer service