Used 1719 Sq Ft. U-Tube Heat Exchanger. Mfg by Bas-Tex Corp 1988. Carbon steel Shell (SA-53-B) rated 150 PSI @ 500 deg F; Carbon Steel Tubes (SA-214) rated 150 PSI @ 500 deg F. Carbon Steel Heads (SA-516). Shell - 1'7" dia. x 17'2"L ; (33) Tubes - 1" dia. Flanged Nozzles: (4) 10", (1) 1", (1) 3/4". S/N: 7249-88-2, NB# 6857.