These fins were designed to be used primarily as a single center fin. #1 Best for areas that have shallow water and or any kind of floating grass/kelp. Effortlessly paddle through thick mats of grass. Transition the shallows of your beach without hitting bottom. Great near shore touring ability. #2 Paddle a course with less effort due to excellent tracking from this design. Glide is enhanced so less side-to-side paddle exchanging is needed. A thin foil section along with a surface piercing leading edge makes this fin fast on all angles. You will find this design to be faster, with less drag than the fin that came stock with your board. A great upgrade fin that has many uses. The SWT is a must have!!