Material: This 5 Gallon Cap is made of silicone material. Flexible, durable, odor-free, and can be used for a long time. More Healthy: Upgrade Non-Spill Plug system, no splash, no leak, sealing strong than general caps, clean and safe to create a sterile environment for crystal-clear water storage. Unique Design: These Bottle Caps adopt a splash-proof design with a strong seal. Make sure the water does not splash, leak, or spill. And keeps the water clean and dust-proof. Reusable Design: Our 5 Gallon Water Bottle Caps can be reused for several times. Say goodbye to single-use water caps, protecting the environment and reducing waste. Wide Application: These Water Bottle Caps can be widely used for any water bottle with a standard opening of 55mm/2.16inch. Material: silicone Size: 5.8*4.5*2.2cm Packing List: 10*Water Bottle Caps