The FuelCATCH prevents the most common cause of fuel being spilled into our oceans, lakes and rivers. Fuel will bubble up and discharge fuel out of the vent on the side of your boat. This device goes over the vent and securely catches leaked fuel so you know when to stop filling your tank. Then once the tank settles you can empty the collect fuel into the fuel fill and put the fuel back in the tank. This concept was introduced as the "Davis No Spill Fuel" Recovery System. Or the "Non Spill". Non linger in production, we continue this legacy of protecting the waterways by giving boaters a easy and convenient way to stop fuel from getting into our waterways. With FuelCATCH you can put covers on the top of the bottle AND the back of the bottle. This allows you to seal up the bottle after you empty it. Stopping drops of fuel from dripping out and damaging the area that you store it. White these improvements it is easier than ever to protect the waterways and your gelcoat from fuel spills out of your fuel vent.