Absorbent soil that prevents sudden intrusion. Easy to use in 4 to 5 minutes. Emergency item that you want to keep in your home for recent rare situations. Not reusable. All you need is water, so you can use it with a water stopping plate, etc. Can be installed in a short amount of time. Perfect for emergencies. Non-slip canvas fabric that is easy to stack. Store in a cool dark place away from water (storage life is not provided, but can be used for about 5 years).