Used Doyle & Roth model VT1661-3VE 125 square foot vertical heat exchanger. Hastelloy C276 tubes rated 150 PSI/full vacuum @ 347 Deg. F. 316L stainless steel shell rated 150 PSI/full vacuum @ 347 Deg. F. Lug Mounted. Built 2000. S/N J9290-12, NB 19069.