MAKE EXERCISE SIMPLE These can improve finger and grip strength for athletes (rock climbing enthusiasts, fitness, tennis, baseball, boxing, tennis, golf and shooting) and musicians (guitar players, bass players, pianists and violinists). It can also relieve some of the tension and anxiety. REHABILITATION and PREVENTION - Your hands probably will get quite sore from using a keyboard and mouse all day and exercising your hands with these egg shape hand therapy balls can definitely solve the issue! It is perfect for your arthritic hands, to build strength without causing injury or pain. You can also use these to try to overcome a habit of picking at hangnails and cracking my knuckles. USE IT ANYWHERE ANYTIME - Our stress relief toys set has a small size and charming egg shape looking. This is a really nice size because you can fit it in your scrub pocket and take it out to squeeze when you need to. You can use it while walking, traveling (car, airplane, bus), in office, school, watching TV, phone calling or any place you want to exercise. SAFE AND DURABLE FOR BOTH CHILD and ADULTS The Hand Exercise Eggs are made of a thermoplastic rubber (TPR), but do not have a strong rubbery odor and are washable in plain water. Completely safe for kids and adults. You might find the egg gets a little bits of sand and lint when it falls into the floor, never mind, it is very easy to be cleaned by washing it under water. GREAT GIFT - The medium is is perfect for the work man with all day work, it can maintain focus and concentration even relieve arthritic hands. The firmest is much suitable for people with certain muscles, like athlete.