Abstract: A heat exchanger fin having enhanced corrugations is provided. The corrugations define a generally sinusoidal wave pattern in a transverse direction across the fin. The fin is particularly well-suited for use in a heat exchanger, such as an evaporator or condenser, in a refrigeration system where the spacing between adjacent fins tends to be greater than in an air conditioning system. For example, when the spacing between adjacent fins is in a range from about 2 to 8 fins per inch, the height of the corrugations is greater than the fin spacing. The greater corrugation height bends the air passing between adjacent fins to a greater extent than prior art corrugated fins, thereby causing a greater volume of air to follow the contours of the corrugations and to come into contact with the surfaces of the fins to enhance heat transfer between the air and the fins. Further, the airflow upstream of the fin collars is defined by a larger vortices than in prior art corrugated fins, which further improves heat transfer.