Is a round multiple torroid composite designed to protect 12 shelterists for long term. The CAT 12 comes standard with an internal 6 KW diesel generator and a 400 gallon fuel tank. It is designed for up to 20 months operation off the local electrical grid. The CAT 12 come with a 1000 gallon water tank and requires a local water well to be drilled to provide a long-term water supply. Enough storage is provided under the floor for over 1400 number #10 cans.