A single fin box is usually found on a longboard and traditional surfboards. A single fin ensures stability and control of your board. Making turns and manoeuvres is a little tricky, however, single fins are ideal for straight and long waves. A single fin box on a longboard is longer than the fin, which makes it possible to place the fin of your preference. If the fin is more in the back of the board, you’ll have more control over your board. With the fin more to the front, you’ll have a looser feeling. Besides this, the shape of the fins is important as well. There’s single fins especially for noseriders, but also for performance longboards. The latter usually have a setup of a single fin plus two small fins. These small fins are called quad rears, which you can find here.
Though, a single fin setup isn’t reserved for just longboards. Traditional surfing often also requires a single fin setup. These boards are around in different models. A single fin on a mid-length makes you glide through the waves, without the need for pumping. Check, for example, the single fins from FCS, Captain Fin and Roam.
Check the Ultimate Surfboard Fin Guide for more information!