Used 135 sq. ft. Lewis Mechanical Shell and Tube Heat Exchanger, all 316L stainless steel construction, including tubes, tube sheets, bonnets and shell, (46) 3/4" diameter x 15' long tubes rated 150 psi at 350 f, shell rated 150 psi at 350 f, 2" shell inlet/outlet, 6" tubes inlet/outlet, single pass, 8" diameter x 15' long tube bundle, serial# 43(125-CE191A), National board# 20, new 1999.