Trainhornkits.net is proud to offer some of the largest air tanks available at the best prices available. These are universal air tanks and are made of rust free steel and can be used both indoor and outdoor. These are a great storage tank for your favorite train horn. Most of our horns are able to withstand Mother Nature's elements, but we do recommomend that these be mounted inside to ensure optimal performance. A few alternative uses for our tanks are air suspension, tire inflation, cleaning, and whatever other uses you can come up with.