Waterproofed, Metal exterior, insulated, metal interior, 6 feet by 14 feet. Faraday room. Cross braced steel I beams through forklift slots on bottom and buried under old semi axles. Anchored through hoist turnbuckles to mobile home screw anchors with stainless aviation cable and buried. 4 vents(2 seen, 2 hidden) 3 points of egress. Sides back filled with scrap metal and topsoil.