Unused 17.5 liters corrugated tube stainless steel heat exchanger. Manufactured by HRS. Model DTA HRS K 7 219/48. Shell material 316L, 253 psi (17.5 bar) max pressure @401F (205C). Tube material 304SS, 65 psi (4.5 bar) max pressure @203 F (95C). Serial #P09741/3-4. Built 2013. Previous use: Heater cooling