Used Yula 3 Pass Shell & Tube Heat Exchanger, Approximately 90 Square Feet, Model WC-3D-168DS, horizontal. Carbon steel shell rated 150 psi at 40 to 250 degrees F. (21) 1-1/4” diameter x 168” long 304L stainless steel tubes rated 150 psi at 40 to 250 degrees F. 304L Stainless steel tubesheet and heads. Openings for tubes (2) 4", openings for shell (2) 4". National Board# 12631, serial# 20261, built 2007.