Suitable Size: each of brain stress balls are measures . 7 cm/ 2.76 inches long, proper size fits hold and grip, suitable for most teens and adults to play and bring people endless funSufficient Quantity: you will get 12 pieces of brain shaped stress balls, quantities to place them , office, in your car or at school to release your stress at any time, and also perfect for exercising your hands and increasing your grip strength, muscle exercise, and moreQuality Material: these fun stress balls for adults are made of quality polyurethane material, without any filling, not easy to break, fun to twist and stretch, good resilience, can be pressed repeatedly, and no irritating smell, suitable for all kinds of hand shapes, and can be applied for a long timeStress and Anxiety Relief: these fun stress relief toys are perfect for relieving tension, stress or anxiety, by pressing on them, your emotions can be vented, and by pressing them to improve concentration and relax your mind and bodyFabulous Gifts: the flexible brain toys are a fun and thoughtful gift for your friend, family, loved ones, colleagues and more; Furthermore, they also can be applied as Halloween prank props, stocking stuffers, party gifts, carnival prizes, school prizes, classroom reward, and so onColor: redMaterial: polyurethanePackage Contents:12 x Brain Stress BallOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.