New heat transfer and draft loss data are presented for one extended surface geometry which was investigated in five staggered and one in-line bank arrangements. In these tests, 1-7/8-inch OD tubes with 1-in. long elliptical studs were investigated. The tube banks, which were in a clean condition, were either 8 or 10 rows deep and covered ratios of transverse spacing to diameter (ST/D) from 2.1 to 3.2 and longitudinal spacing to diameter (ST/D) from 1.7 to 2.4. Heat transfer was from air to the tube banks, with Reynolds numbers ranging from 13,700 to 46,400. Correlations with suitable arrangement factors are shown to adequately describe the performance of the surface investigated. The relative heat transfer, draft loss performance of all arrangements is shown to depend upon the basis of comparison used.