Used Atlas approximately 21 sq. ft. horizontal shell and tube heat exchanger. 5 9/16" diameter X 7'-9" overall length. Carbon steel shell rated 100 PSI @ -20 to 200 degrees F. T-316 L tubes rated 75/FV @ -20 to 300 degrees F. T-316 L welded tubsheets are 5.2945" diameter X 3/4" thick. Contains (18) 3/4" OD tubes made of 18 GA T-316 L. NB# 6827. Serial # 8175. Built 1992. Equipped with (12) 1/8" carbon steel baffles. Mounted on carbon steel feet giving 5 degree incline.