Abstract: An improved atmospheric vaporizer/heat exchanger adapted for vaporizing cryogenic liquids includes a heat exchange element having a tube through which the cryogenic fluid flows and a plurality of fins attached to the tube. At least some of the fins include on their edges a rail or like member which has substantially flat surfaces. Brackets interconnect the fins of the heat exchange elements through channel shaped members disposed on two parallel edges. The channel shaped members of the brackets are configured to be complementary to the rails and have complementary substantially flat surface which mate with the matching flat surfaces of the rails and thereby substantially prevent rotation of the heat exchange elements relative to the brackets. After assembly, the matching rails and channels are deformed in sections by crimping or the like, to prevent sliding of the brackets on the rails and to obtain a finally assembled structure.