Soft silicone material, enviromental friendly. Lightweight racquet vidampener easily installs. It can absorbs a ton of vibration, sound. They are brilliant affordable gifts for anyone, young, old, teens. These vibrastops will evoke a smile from the recipient for sure. Kids will love them! Customize the design, colors are welcome. Our premium durable dampeners improve your comfort consistency in every shot while reducing shock to your wrist elbow. These do not fall off the string!