Quantity:You will receive 6pcs tennis ball vibration dampener Size:The Silicone Dampener diameter is About 0.9 Inch / 2.3cm,please check the size before purchase Material: They are all made of high quality silicone, well made, reliable quality, light weight, small size, easy to carry, not easy to deform, tear and break, can be stored for a long time; smooth surface of the shock absorber, comfortable to touch, no need to worry about scratching your fingers. Easy to use:It is easy to install and helps with vibration when hitting the tennis ball with minimal detachment issues and zero blowouts. Protection:Practical tennis racket shock absorber can effectively reduce the vibration generated when hitting the ball, protect your arm from shock and vibration, thus protecting your elbow and maintaining stability. The tennis dampener can effectively reduce the vibration generated by the ball hitting the string to increase comfort. With this shock absorber, you can obviously feel the reduction of the vibration and the change of the residual sound at the moment of hitting.